Turret operator interface system and method for a fire fighting vehicle

ABSTRACT

A turret control system includes one or more control modules, such as an envelope control module, turret targeting module, a turret pan module, a turret deploy module, a turret store module. The preferred turret control system also provides improved turret control flexibility and improved operator feedback.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Prov. No. 60/360,479, filedFeb. 28, 2002, entitled “Turret Control System and Method for a FireFighting Vehicle,” and to U.S. Prov. No. 60/388,451, filed Jun. 13,2002, entitled “Control System and Method for an Equipment ServiceVehicle,” each of which is hereby expressly incorporated by reference.This application is also a continuation-in-part of U.S. Ser. No.10/326,907, filed Dec. 20, 2002, entitled “Firefighting Vehicle withNetwork-Assisted Scene Management,” U.S. Ser. No. 10/326,907 is acontinuation-in-part of U.S. Ser. No. 09/927,946, filed Aug. 10, 2001,entitled “Military Vehicle Having Cooperative Control Network WithDistributed I/O Interfacing,” which is a continuation-in-part of U.S.Ser. No. 09/384,393, filed Aug. 27, 1999, entitled “Military VehicleHaving Cooperative Control Network With Distributed I/O Interfacing,”now U.S. Pat. No. 6,421,593, which is a continuation-in-part of U.S.Ser. No. 09/364,690, filed Jul. 30, 1999, entitled “Firefighting VehicleHaving Cooperative Control Network With Distributed I/O Interfacing,”abandoned, each of which is hereby expressly incorporated by reference;and is also a continuation-in-part of U.S. Ser. No. 09/500,506, filedFeb. 9, 2000 now U.S. Pat. No. 6,553,290, entitled “Equipment ServiceVehicle Having On-Board Diagnostic System,” also expressly incorporatedby reference; and also claims priority to U.S. Prov. No. 60/342,292,filed Dec. 21, 2001, entitled “Vehicle Control and Monitoring System andMethod,” also hereby expressly incorporated by reference.

FIELD OF THE INVENTION

The present invention relates generally to the field of fire fightingvehicles. More specifically, the present invention relates to turretcontrol systems and methods for fire fighting vehicles.

BACKGROUND OF THE INVENTION

Various vehicles are known for use in fire fighting. Fire fightingvehicles, including aerial platform trucks, ladder trucks, pumpers,tankers, etc., often employ a turret for dispensing fire fighting agents(e.g. water, foams, foaming agents, etc.) onto areas such as fires,chemical spills, smoldering remains of a fire, or other similar areas.Such turrets typically comprise one or more arms which are extendable,rotatable, or otherwise moveable with electric, hydraulic, or pneumaticactuator systems. While fighting a fire, the turret may be moved aroundin a three-dimensional space by using the actuator system to moveindividual arms. Once a nozzle of the turret is brought to a particularposition and orientation relative to a fire, a fire fighting agent maybe dispensed from the nozzle and directed at the fire.

Typically, this positioning and aiming of turrets is controlled by ahuman operator. According to one approach, the operator positions andaims the turret using a joystick which is coupled to the turretactuators. Unfortunately, in situations where the fire produces a largeamount of smoke, the turret and the precise location of the fire becomeobscured from an operator's view. This situation is exacerbated by thefact that the tremendous flow of water or other fire fighting agentthrough the turret creates forces which affect turret positioning,making it even more difficult for the operator to know the preciseposition of the turret. The result is that the operator is oftensusceptible to inadvertently causing the turret to collide with otherobjects, including for example the fire fighting vehicle upon which theturret is mounted. Additionally, because the operator's view of theturret nozzle as well as the fire may be severely limited, theoperator's ability to control the position and orientation of the nozzlefor maximum fire fighting effectiveness is also severely limited.

Further, existing turret systems are often cumbersome or difficult tooperate. For example, turret systems typically allow the turret to bemanually stored and locked into place to avoid damage during vehicletravel. However, the process of storing and locking the turret can betime consuming because the proximity of the turret to other equipment onthe fire fighting vehicle requires that the turret be controlled withgreat care. Additionally, when the fire fighting vehicle arrives at thescene of the fire and the turret is first deployed, it is necessary fora fire fighter to manually deploy the turret from the stored position,thereby diverting the fire fighter's attention away from other importantactivities. Finally, the operator interface used to control the turretlimits the operator's ability to control the turret from a variety ofdifferent vantage points and with the benefit of a variety of differentviews of the turret and the fire. A variety of other problems existwhich relate to the difficulty and/or amount of operator involvementrequired to operate turrets.

Accordingly, it would be desirable to provide a control system for aturret which overcomes one or more of the above-mentioned problems.Advantageously, such a control system would enhance fire fighter safetyby increasing fire fighting effectiveness. The techniques below extendto those embodiments which fall within the scope of the appended claims,regardless of whether they provide any of the above-mentionedadvantageous features.

SUMMARY OF THE INVENTION

According to a first aspect, a method of controlling a fire fightingvehicle having a turret comprises determining a location of a region ofinterest of a fire and adjusting a position and orientation of a nozzleof the turret responsive to the determining step. The adjusting step isperformed using a turret motion controller.

According to a second aspect, a method of controlling motion of a turreton a fire fighting vehicle comprises acquiring operator inputs andpreventing the turret from impacting the fire fighting vehicle. Theoperator inputs are useable to generate first control signals to controlmotion of the turret. The operator inputs direct movement of the turretin such a way that the turret is susceptible to impacting the firefighting vehicle. The preventing step includes determining that theturret is susceptible to impacting the fire fighting vehicle, and inresponse providing the turret-with second control signals that aredifferent than the first control signals. The second control signalsdirect movement of the turret in such a way that the turret does notimpact the fire fighting vehicle.

According to a third aspect, a method of controlling a turret mounted ona fire fighting vehicle comprises storing information in a turret motioncontroller. The information pertains to desired movement of the turret.The method further comprises controlling movement of the turret usingthe turret motion controller. The movement of the turret is controlledin accordance with the information.

Other objects, features, and advantages of the present invention willbecome apparent to those skilled in the art from the following detaileddescription and accompanying drawings. It should be understood, however,that the detailed description and specific examples, while indicatingpreferred embodiments of the present invention, are given by way ofillustration and not limitation. Many modifications and changes withinthe scope of the present invention may be made without departing fromthe spirit thereof, and the invention includes all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a fire truck having a control systemaccording to one embodiment of the present invention;

FIG. 2 is a block diagram of the control system of FIG. 1 showingselected aspects of the control system in greater detail;

FIG. 3 is a schematic view of an aerial device having a control systemaccording to another embodiment of the present invention;

FIG. 4 is a more detailed block diagram of the control system of FIG. 3;

FIG. 5 is a schematic view of a vehicle having a control systemaccording to another embodiment of the present invention;

FIGS. 6–7 are block diagrams of the control system of FIG. 5 showingselected aspects of the control system in greater detail;

FIG. 8 is a diagram showing the memory contents of an exemplaryinterface module in greater detail;

FIG. 9 is a block diagram of the control system of FIG. 5 showingselected aspects of the control system in greater detail;

FIG. 10 is an I/O status table of FIG. 9 shown in greater detail;

FIG. 11 is a flowchart describing the operation of the control system ofFIG. 9 in greater detail;

FIG. 12 is a data flow diagram describing data flow through an exemplaryinterface module during the process of FIG. 11;

FIG. 13 is a block diagram of a fire fighting control system capable ofcontrolling a turret;

FIG. 14 is a schematic representation of a turret;

FIG. 15 is a block diagram of turret I/O devices connected to interfacemodules in the control system of FIG. 13;

FIG. 16 is a block diagram showing selected aspects functions of thecontrol system of FIG. 13 in greater detail;

FIG. 17 is a flowchart showing a method for constraining a turret to apermissible travel envelope;

FIG. 18 is a flowchart showing a method for determining the position ofthe turret relative to the permissible travel envelope in connectionwith the method of FIG. 17;

FIG. 19 is a flowchart showing a method for determining the position ofthe turret relative to the permissible travel envelope in connectionwith the method of FIG. 17;

FIG. 20 is a block diagram of a first embodiment of a fire positionindicator in the block diagram of FIG. 16;

FIG. 21 is a block diagram of a second embodiment of a fire positionindicator in the block diagram of FIG. 16;

FIG. 22 is a flowchart showing operation of a turret targeting module inthe block diagram of FIG. 16;

FIGS. 23–24 are flowcharts showing operation of turret learn and turretpan modules in the block diagram of FIG. 16;

FIG. 25 is a block diagram showing a feedback control system of FIG. 16in greater detail;

FIG. 26 is a block diagram of a turret control system that controlsfirst and second turrets; and

FIG. 27 is a block diagram of a flow rate control system for the turretof FIG. 14.

DETAILED DESCRIPTION OF ADDITIONAL EMBODIMENTS

Patent application Ser. No. 09/384,393, filed Aug. 27, 1999, now U.S.Pat. No. 6,421,593, discloses various embodiments of a control systemarchitecture in connection with fire trucks and other types of equipmentservice vehicles. The turret control systems and methods disclosedherein may be implemented using a stand-alone control system or usingone of the control system architecture embodiments described in theaforementioned application. For convenience, the contents of theabove-mentioned application is repeated below, followed by a descriptionof a preferred turret control system and method for a fire fightingvehicle.

A. Fire Truck Control System

1. Architecture of Fire Truck Control System

Referring now to FIG. 1, a fire truck 10 having a control system 12 isillustrated. By way of overview, the control system 12 comprises acentral control unit 14, a plurality of microprocessor-based interfacemodules 20 and 30, a plurality of input devices 40 and a plurality ofoutput devices 50. The central control unit 14 and the interface modules20 and 30 are connected to each other by a communication network 60.

More specifically, the central control unit 14 is a microprocessor-baseddevice and includes a microprocessor 15 that executes a control program16 (see FIG. 2) stored in memory of the central control unit 14. Ingeneral, the control unit 14 executes the program to collect and storeinput status information from the input devices 40, and to control theoutput devices 50 based on the collected status information. The controlprogram may implement such features as an interlock system, a loadmanager, and a load sequencer. As described below, the central controlunit 14 is preferably not connected to the I/O devices 40 and 50directly but rather only indirectly by way of the interface modules 20and 30, thereby enabling distributed data collection and powerdistribution. The I/O devices 40 and 50 are located on a chassis 11 ofthe fire truck 10, which includes both the body and the underbody of thefire truck 10.

In the illustrated embodiment, two different types of interface modulesare used. The interface modules 20 interface mainly with switches andlow power indicators, such as LEDs that are integrally fabricated with aparticular switch and that are used to provide visual feedback to anoperator regarding the state of the particular switch. For this reason,the interface modules 20 are sometimes referred to herein as “SIMs”(“switch interface modules”). Herein, the reference numeral “20” is usedto refer to the interface modules 20 collectively, whereas the referencenumerals 21, 22 and 23 are used to refer to specific ones of theinterface modules 20.

The interface modules 30 interface with the remaining I/O devices 40 and50 on the vehicle that do not interface to the interface modules 20, andtherefore are sometimes referred to herein as “VIMs” (“vehicle interfacemodules”). The interface modules 30 are distinguishable from theinterface modules 20 mainly in that the interface modules 30 are capableof handling both analog and digital inputs and outputs, and in that theyare capable of providing more output power to drive devices such asgauges, valves, solenoids, vehicle lighting and so on. The analogoutputs may be true analog outputs or they may be pulse width modulationoutputs that are used to emulate analog outputs. Herein, the referencenumeral “30” is used to refer to the interface modules 30 collectively,whereas the reference numerals 31, 32, 33, 34 and 35 are used to referto specific ones of the interface modules 30.

Although two different types of interface modules are used in theillustrated embodiment, depending on the application, it may bedesirable to use only a single type of interface module in order toreduce inventory requirements. Additionally, while in FIG. 1 three ofthe interface modules 20 and five of the interface modules 30 are shown,this arrangement is again simply one example. It may be desirable toprovide each interface module with more I/O points in order to reducethe number of interface modules that are required, or to use moreinterface modules with a smaller number of I/O points in order to makethe control system 12 more highly distributed. Of course, the number ofinterface modules will also be affected by the total number of I/Opoints in the control system.

FIG. 1 shows an approximate distribution of the interface modules 20 and30 throughout the fire truck 10. In general, in order to minimizewiring, the interface modules 20 and 30 are placed so as to be locatedas closely as possible to the input devices 40 from which input statusinformation is received and the output devices 50 that are controlled.As shown in FIG. 1, there is a large concentration of interface modules20 and 30 near the front of the fire truck 10, with an additionalinterface module 34 at mid-length of the fire truck 10 and anotherinterface module 35 at the rear of the fire truck 10. The largeconcentration of interface modules 20 and 30 at the front of the firetruck 10 is caused by the large number of switches (including those withintegral LED feedback output devices) located in a cab of the fire truck10, as well as the large number of other output devices (gauges,lighting) which tend to be located in the cab or otherwise near thefront of the fire truck 10. The interface module 34 that is located inthe middle of the truck is used in connection with I/O devices 40 and 50that are located at the fire truck pump panel (i.e., the operator panelthat has I/O devices for operator control of the fire truck's pumpsystem). The interface module 35 that is located at the rear of the firetruck 10 is used in connection with lighting and other equipment at therear of the fire truck 10.

The advantage of distributing the interface modules 20 and 30 in thismanner can be more fully appreciated with reference to FIG. 2, whichshows the interconnection of the interface modules 20 and 30. As shownin FIG. 2, the interface modules 20 and 30 receive power from a powersource 100 by way of a power transmission link 103. The powertransmission link 103 may comprise for example a single power line thatis routed throughout the fire truck 10 to each of the interface modules20 and 30. The interface modules then distribute the power to the outputdevices 50, which are more specifically designated with the referencenumbers 51 a, 52 a, 53 a, 54 a–c, 55 a–c, 56 a–b, 57 a–c and 58 a–d inFIG. 2.

It is therefore seen from FIGS. 1 and 2 that the relative distributionof the interface modules 20 and 30 throughout the fire truck 10 incombination with the arrangement of the power transmission link 103allows the amount of wiring on the fire truck 10 to be dramaticallyreduced. The power source 100 delivers power to the interface modules 20and 30, which act among other things as power distribution centers, andnot directly to the output devices 50. Because the interface modules 20and 30 are located so closely to the I/O devices 40 and 50, most of theI/O devices can be connected to the interface modules 20 and 30 usingonly a few feet of wire or less. This eliminates the need for a wireharness that extends the length of the fire truck (about forty feet) toestablish connections for each I/O devices 40 and 50 individually.

Continuing to refer to FIG. 2, the switch interface modules 20 and theinterconnection of the interface modules 20 with various I/O deviceswill now be described in greater detail. The interface modules 20 aremicroprocessor-based, as previously noted, and include a microprocessorthat executes a program to enable communication over the communicationnetwork 60, as detailed below.

The same or a different microprocessor of the interface modules 20 mayalso be used to process input signals received from the input devices40. In particular, the interface modules 20 preferably perform debouncefiltering of the switch inputs, so as to require that the position ofthe switch become mechanically stable before a switch transition isreported to the central control unit 14. For example, a delay of fiftymilliseconds may be required before a switch transition is reported.Performing this filtering at the interface modules 20 reduces the amountof processing that is required by the central control unit 14 tointerpret switch inputs, and also reduces the amount of communicationthat is required over the communication network 60 because each switchtransition need not be reported.

Physically, the interface modules 20 may be placed near the headliner ofa cab 17 of the fire truck 10. Traditionally, it is common practice tolocate panels of switches along the headliner of the cab for easy accessby an operator of the fire truck. Additionally, as detailed below, inthe preferred embodiment, the interface modules 20 are connected toswitches that have integrally fabricated LEDs for indicating the stateof the output device controlled by the switch to provide maximumoperator feedback. These LEDs are output devices which are connected tothe interface modules 20. Therefore, by locating the interface modulesnear the headliner of the cab, the amount of wiring required to connectthe interface modules 20 not only to the switches and but also to theLED indicators is reduced.

In the preferred embodiment, the interface modules 20 have between tenand twenty-five each of inputs and outputs and, more preferably, havesixteen digital (on/off switch) inputs and sixteen LED outputs. Most ofthese inputs and outputs are utilized in connection with switches havingintegrally fabricated LEDs. However, it should be noted that there neednot be a one-to-one correspondence between the switches and the LEDs,and that the inputs and the outputs of the interface modules 20 need notbe in matched pairs. For example, some inputs may be digital sensors(without a corresponding output device) and some of the outputs may beordinary digital indicators (without a corresponding input device).Additionally, the LED indicators associated with the switch inputs forthe interface module 21 could just as easily be driven by the interfacemodule 23 as by the interface module 21, although this arrangement isnot preferred. Of course, it is not necessary that all of the inputs andoutputs on a given interface module 20 be utilized and, in fact, it islikely that some will remain unutilized.

One way of establishing a dedicated link between the I/O devices 40 and50 and the interface modules 20 is through the use of a simple hardwiredlink. Considering for example an input device which is a switch, oneterminal of the switch may be connected (e.g., by way of a harnessconnector) to an input terminal of the interface module 20 and the otherterminal of the switch may be tied high (bus voltage) or low (ground).Likewise, for an output device which is an LED, one terminal of the LEDmay be connected to an output terminal of the interface module 20 andthe other terminal of the LED may again be tied high or low. Otherdedicated links, such as RF links, could also be used.

To provide maximum operator feedback, the LEDs that are located with theswitches have three states, namely, off, on, and blinking. The off stateindicates that the switch is off and therefore that the devicecontrolled by the switch is off. Conversely, the on state indicates thatthe switch is on and that the device controlled by the switch is on. Theblinking state indicates that the control system 12 recognizes that aswitch is on, but that the device which the switch controls isnevertheless off for some other reason (e.g., due to the failure of aninterlock condition, or due to the operation of the load manager or loadsequencer). Notably, the blinking LED feedback is made possible by thefact that the LEDs are controlled by the control unit 14 and notdirectly by the switches themselves, since the switches themselves donot necessarily know the output state of the devices they control.

A specific example will now be given of a preferred interconnection ofthe interface modules 21, 22, and 23 with a plurality of I/O devices 40and 50. Many or all of the I/O devices 40 and 50 could be the same asthose that have previously been used on fire trucks. Additionally, itshould be noted that the example given below is just one example, andthat a virtually unlimited number of configurations are possible. Thisis especially true since fire trucks tend to be sold one or two at atime and therefore each fire truck that is sold tends to be unique atleast in some respects.

In FIG. 2, the interface module 21 receives inputs from switches 41 athat control the emergency lighting system of the fire truck. Aspreviously noted, the emergency lighting system includes the flashingemergency lights (usually red and white) that are commonly associatedwith fire trucks and that are used to alert other motorists to thepresence of the fire truck on the roadway or at the scene of a fire. Oneof the switches 41 a may be an emergency master on/off (E-master) switchused to initiate load sequencing, as described in greater detail below.The interface module 21 may also be connected, for example, to switches41 b that control the emergency siren and horn. The interface module 21is also connected to LEDs 51 a that are integrally located in theswitches 41 a and 41 b and that provide operator feedback regarding thepositions of the switches 41 a and 41 b, as previously described.

The interface module 22 receives inputs from switches 42 a that controllighting around the perimeter of the fire truck 10, switches 42 b thatcontrol scene lighting, and switches 42 c that control lighting whichaids the operators in viewing gauges and other settings at the pumppanel. The interface module 22 is also connected to LEDs 52 a that areintegrally located in the switches 42 a, 42 b and 42 c and that provideoperator feedback regarding the positions of the switches 42 a, 42 b and42 c.

The interface module 23 receives inputs from switches 43 a that controlheating and air conditioning, and switches 43 b that controlsmiscellaneous other electrical devices. The interface module 23 isconnected to LED indicators, some of which may be integrally locatedwith the switches 43 a and 43 b and others of which may simply be an LEDindicator that is mounted on the dashboard or elsewhere in the cab ofthe fire truck 10.

Continuing to refer to FIG. 2, the vehicle interface modules 30 and theinterconnection of the interface modules 20 with various I/O deviceswill now be described in greater detail. As previously mentioned, theinterface modules 30 are distinguishable from the interface modules 20mainly in that the interface modules 30 are capable of handling bothanalog and digital inputs and outputs, and in that they are capable ofproviding more output power to drive output devices such asdigitally-driven gauges, solenoids, and so on. The interface modules 30preferably have between fifteen and twenty-five each inputs and outputsand, more preferably, have twenty inputs (including six digital inputs,two frequency counter inputs, and six analog inputs) and twenty outputs(including six outputs that are configurable as analog outputs).

Like the interface modules 20, the interface modules 30 aremicroprocessor-based and include a microprocessor that executes aprogram to enable communication over the communication network 60. Thesame or a different microprocessor of the interface modules 30 may alsobe used to process input signals received from the input devices 40 andto process output signals transmitted to the output devices 50.

For the interface modules 30, this processing includes not only debouncefiltering, in the case of switch inputs, but also a variety of othertypes of processing. For example, for analog inputs, this processingincludes any processing that is required to interpret the inputs fromanalog-to-digital (A/D) converters, including converting units. Forfrequency inputs, this processing includes any processing that isrequired to interpret inputs from frequency-to-digital converters,including converting units. This processing also includes other simplefiltering operations. For example, in connection with one analog input,this processing may include notifying the central control unit 14 of thestatus of an input device only every second or so. In connection withanother analog input, this processing may include advising the centralcontrol unit 14 only when the status of the input device changes by apredetermined amount. For analog output devices, this processingincludes any processing that is required to interpret the outputs fordigital-to-analog (D/A) converters, including converting units. Fordigital output devices that blink or flash, this processing includesimplementing the blinking or flashing (i.e., turning the output deviceon and off at a predetermined frequency) based on an instruction fromthe central control unit 14 that the output device should blink orflash. In general, the processing by the interface modules 30 reducesthe amount of information which must be communicated over thecommunication link, and also reduces the amount of time that the centralcontrol unit 14 must spend processing minor changes in analog inputstatus.

Preferably, the configuration information required to implement the I/Oprocessing that has just been described is downloaded from the centralcontrol unit 14 to each interface module 30 (and each interface module20) at power-up. Additionally, the harness connector that connects toeach of the interface modules 20 and 30 are preferably electronicallykeyed, such that being connected to a particular harness connectorprovides the interface modules 20 and 30 with a unique identificationcode (for example, by tying various connector pins high and low toimplement a binary code). The advantage of this approach is that theinterface modules 20 and 30 become interchangeable devices that arecustomized only at power-up. As a result, if one of the interfacemodules 30 malfunctions, for example, a new interface module 30 can beplugged into the control system 12, customized automatically at power-up(without user involvement), and the control system 12 then becomes fullyoperational. This enhances the maintainability of the control system 12.

A specific example will now be given of a preferred interconnection ofthe interface modules 31, 32, and 33 with a plurality of I/O devices 40and 50. This example continues the example that was started inconnection with the interface modules 21, 22, and 23. Again, it shouldbe noted that the configuration described herein is just one example.

The interface modules 31, 32, 33, 34 and 35 all receive inputs fromadditional switches and sensors 44 a, 45 a, 46 a, 47 a and 48 a. Theswitches may be additional switches that are located in the cab of thefire truck or elsewhere throughout the vehicle, depending on thelocation of the interface module. The sensors may be selected ones of avariety of sensors that are located throughout the fire truck. Thesensors may be used to sense the mechanical status of devices on thefire truck, for example, whether particular devices are engaged ordisengaged, whether particular devices are deployed, whether particulardoors on the fire truck are open or closed, and so on. The sensors mayalso be used to sense fluid levels such as fuel level, transmissionfluid level, coolant level, foam pressure, oil level, and so on.

In addition to the switches and sensors 44 a, the interface module 31 isalso connected to a portion 54 a of the emergency lighting system. Theemergency lighting system includes emergency lights (usually red andwhite) at the front, side and rear of the fire truck 10. The emergencylights may, for example, be in accordance with the guidelines providedby the National Fire Protection Association. Because the interfacemodule 31 is located at the front of the fire truck, the interfacemodule 31 is connected to the red and white emergency lights at thefront of the fire truck.

The interface module 31 is also connected to gauges and indicators 54 bwhich are located on the dashboard of the fire truck 10. The gauges mayindicate fluid levels such as fuel level, transmission fluid level,coolant level, foam pressure, oil level and so on. The indicators mayinclude, for example, indicators that are used to display danger,warning and caution messages, warning lights, and indicators thatindicate the status of various mechanical and electrical systems on thefire truck. The interface module 31 may also be connected, for example,to an emergency sound system including an emergency siren and emergencyair horns 54 c, which are used in combination with the emergency lights54 a.

In addition to the switches and sensors 45 a, the interface module 32 isalso connected to perimeter lighting 55 a, scene lighting 55 b andutility lighting 55 c. The perimeter lighting 55 a illuminates theperimeter of the fire truck 10. The scene lighting 55 b includes brightflood lights and/or spot lights to illuminate the work area at a fire.The utility lighting 55 c includes lighting used to light operatorpanels, compartments and so on of the fire truck 10.

In addition to the switches and sensors 46 a, the interface module 33 isalso connected to PTO sensors 46 b. The PTO sensors 46 b monitor thestatus of a power take-off mechanism 97 (see FIG. 1), which divertsmechanical power from the engine/transmission from the wheels to othermechanical subsystems, such as the pump system, an aerial system and soon. The interface module 33 is also connected to a portion 56 a of theFMVSS (Federal Motor Vehicle Safety Standard) lighting. The FMVSSlighting system includes the usual types of lighting systems that arecommonly found on most types of vehicles, for example, head lights, taillights, brake lights, directional lights (including left and rightdirectionals), hazard lights, and so on. The interface module 33 is alsoconnected to the heating and air conditioning 56 b.

In addition to the switches and sensors 47 a, the interface module 34,which is disposed near the pump panel, is connected to pump panelswitches and sensors 47 a, pump panel gauges and indicators 57 a, pumppanel lighting 57 b, and perimeter lighting 57 c. The pump system may bemanually controlled or may be automatically controlled through the useof electronically controlled valves. In either case, the various fluidpressures are measured by sensors and displayed on the gauges andindicators 57 a.

Finally, in addition to the switches and sensors 48 a, the interfacemodule 35 is also connected to emergency lighting 58 a, scene lighting58 b, FMVSS lighting 58 c, and the utility lighting 58 d. These lightingsystems have been described above.

The interface modules 20 and the interface modules 30 are connected tothe central control unit 14 by the communication network 60. Thecommunication network may be implemented using a network protocol, forexample, which is in compliance with the Society of Automotive Engineers(SAE) J1708/1587 and/or J1939 standards. The particular network protocolthat is utilized is not critical, although all of the devices on thenetwork should be able to communicate effectively and reliably.

The transmission medium may be implemented using copper or fiber opticcable. Fiber optic cable is particularly advantageous in connection withfire trucks because fiber optic cable is substantially immune toelectromagnetic interference, for example, from communication antennaeon mobile news vehicles, which are common at the scenes of fires.Additionally, fiber optic cable is advantageous because it reduces RFemissions and the possibility of short circuits as compared tocopper-based networks. Finally, fiber optic cable is advantageousbecause it reduces the possibility of electrocution as compared tocopper in the event that the cable accidentally comes into contact withpower lines at the scene of a fire.

Also connected to the communication network 60 are a plurality ofdisplays 81 and 82. The displays 81 and 82 permit any of the datacollected by the central control unit 14 to be displayed to thefirefighters in real time. In practice, the data displayed by thedisplays 81 and 82 may be displayed in the form of text messages and maybe organized into screens of data (given that there is too much data todisplay at one time) and the displays 81 and 82 may include membranepushbuttons that allow the firefighters to scroll through, page through,or otherwise view the screens of data that are available. Additionally,although the displays 81 and 82 are both capable of displaying any ofthe information collected by the central control unit 14, in practice,the displays 81 and 82 are likely to be used only to display selectedcategories of information. For example, assuming the display 81 islocated in the cab and the display 82 is located at the pump panel, thedisplay 81 is likely to be used to display information that pertains todevices which are controlled from within the cab, whereas the display 82is likely to be used to display information pertaining to the operationof the pump panel. Advantageously, the displays 81 and 82 givefirefighters instant access to fire truck information at a singlelocation, which facilitates both normal operations of the fire truck aswell as troubleshooting if problems arise.

Also shown in FIG. 2 is a personal computer 85 which is connected to thecontrol unit 14 by way of a communication link 86, which may be a modemlink, an RS-232 link, an Internet link, and so on. The personal computer85 allows diagnostic software to be utilized for remote or localtroubleshooting of the control system 12, for example, through directexamination of inputs, direct control of outputs, and viewing andcontrolling internal states, including interlock states. Because all I/Ostatus information is stored in the central control unit 14, thisinformation can be easily accessed and manipulated by the personalcomputer 85. If a problem is encountered, the personal computer can beused to determine whether the central control unit 14 considers all ofthe interface modules 20 and 30 to be “on-line” and, if not, theoperator can check for bad connections and so on. If a particular outputdevice is not working properly, the personal computer 85 can be used totrace the I/O status information from the switch or other input devicethrough to the malfunctioning output device. For example, the personalcomputer 85 can be used to determine whether the switch state is beingread properly, whether all interlock conditions are met, and so on.

The personal computer 85 also allows new firmware to be downloaded tothe control unit 14 remotely (e.g., from a different city or state orother remote location by way of the Internet or a telephone link) by wayof the communication link 86. The firmware can be firmware for thecontrol unit 14, or it can be firmware for the interface modules 20 and30 that is downloaded to the control unit 14 and then transmitted to theinterface modules 20 and 30 by way of the communication network 60.

Finally, referring back to FIG. 1, several additional systems are shownwhich will now be briefly described before proceeding to a discussion ofthe operation of the control system 12. In particular, FIG. 1 shows anengine system including an engine 92 and an engine control system 91, atransmission system including a transmission 93 and a transmissioncontrol system 94, and an anti-lock brake system including an anti-lockbrake control system 95 and anti-lock brakes 96. The transmission 93 ismechanically coupled to the engine 92, and is itself furthermechanically coupled to a PTO system 97. The PTO system 97 allowsmechanical power from the engine to be diverted to water pumps, aerialdrive mechanisms, stabilizer drive mechanisms, and so on. Incombination, the engine system, the transmission system and the PTOsystem form the power train of the fire truck 10.

The control systems 92, 94 and 95 may be connected to the centralcontrol unit 14 using the same or a different communication network thanis used by the interface modules 30 and 40. In practice, the controlsystems 92, 94 and 95 are likely to be purchased as off-the-shelfsystems, since most fire truck manufacturers purchase rather thanmanufacture engine systems, transmission systems and anti-lock brakesystems. As a result, it is likely that the control systems 92, 94 and95 will use a variety of different communication protocols and thereforethat at least one additional communication network will be required.

By connecting the systems 92, 94 and 95 to the central control unit 14,an array of additional input status information becomes available to thecontrol system 12. For example, for the engine, this allows the centralcontrol unit 14 to obtain I/O status information pertaining to enginespeed, engine hours, oil temperature, oil pressure, oil level, coolantlevel, fuel level, and so on. For the transmission, this allows thecentral control unit 14 to obtain, for example, information pertainingtransmission temperature, transmission fluid level and/or transmissionstate (1st gear, 2nd gear, and so on). Assuming that an off-the-shelfengine or transmission system is used, the information that is availabledepends on the manufacturer of the system and the information that theyhave chosen to make available.

Connecting the systems 92, 94 and 95 to the central control unit 14 isadvantageous because it allows information from these subsystems to bedisplayed to firefighters using the displays 81 and 82. This also allowsthe central control unit 14 to implement various interlock conditions asa function of the state of the transmission, engine or brake systems.For example, in order to turn on the pump system (which is mechanicallydriven by the engine and the transmission), an interlock condition maybe implemented that requires that the transmission be in neutral or 4thlockup (i.e., fourth gear with the torque converter locked up), so thatthe pump can only be engaged when the wheels are disengaged from thepower train. The status information from these systems can therefore betreated in the same manner as I/O status information from any otherdiscrete I/O device on the fire truck 10. It may also be desirable toprovide the central control unit 14 with a limited degree of controlover the engine and transmission systems, for example, enabling thecentral control unit 14 to issue throttle command requests to the enginecontrol system 91. This allows the central control unit to control thespeed of the engine and therefore the voltage developed across thealternator that forms part of the power source 100.

2. Aerial Control

Referring now to FIG. 3, a preferred embodiment of a fire truck 1210with an aerial 1211 having an aerial control system 1212 is illustrated.By way of overview, the control system 1212 comprises an aerial centralcontrol unit 1214, a plurality of microprocessor-based interface modules1220, 1230 and 1235, a plurality of input devices 1240, and a pluralityof output devices 1250. The central control unit 1214 and the interfacemodules 1220, 1230 and 1235 are connected to each other by acommunication network 1260.

The control system 1212 is similar in most respect to the control system12, with the primary difference being that the control system 1212 isused to control the output devices 1250 on the aerial 1211 based oninput status information from the input devices 1240, rather than tocontrol the output devices 50 on the chassis 11. The interface modules1220 and 1230 may be identical to the interface modules 20 and 30,respectively, and the central control unit 1214 may be identical to thecentral control unit 14 except that a different control program isrequired in connection with the aerial 1211. Accordingly, the discussionabove regarding the interconnection and operation of the interfacemodules 20 and 30 with the input devices 40 and output devices 50applies equally to the central control unit 1214, except to the extentthat the control system 1212 is associated with the aerial 1211 and notwith the chassis 11.

The aerial control system 1212 also includes the interface modules1225–1227, which are similar to the interface modules 20 and 30 exceptthat different I/O counts are utilized. In the preferred embodiment, theinterface modules 1225–1227 have twenty-eight switch inputs (two ofwhich are configurable as frequency inputs). As previously noted, ratherthan using several different types of interface modules, it may bedesirable to use only a single type of interface module in order toreduce inventory requirements. Additionally, the number of interfacemodules and the I/O counts are simply one example of a configurationthat may be utilized.

It is desirable to use a control system 1212 for the aerial 1211 whichis separate from the control system 12 in order to provide a clearseparation of function between systems associated with the aerial 1211and systems associated with the chassis 11. Additionally, as a practicalmatter, many fire trucks are sold without aerials and thereforeproviding a separate aerial control system enables a higher levelcommonality with respect to fire trucks that have aerials and firetrucks that do not have aerials.

With reference to FIG. 4, a specific example will now be given of apreferred interconnection of the interface modules with a plurality ofinput devices 1240 and output devices 1250. The interface module 1221receives inputs from switches 1241 a which may include for example anaerial master switch that activates aerial electrical circuits, anaerial PTO switch that activates the transmission to provide rotationalinput power for the hydraulic pump, and a platform leveling switch thatmomentarily activates a platform (basket) level electrical circuit tolevel the basket relative to the current ground grade condition. The LEDindicators 1251 provide visual feedback regarding the status of theinput switches 1241 a.

The interface modules 1225 and 1231 are located near a ground-levelcontrol station at a rear of the fire truck 10. The interface modules1225 and 1231 receive inputs from switches 1242 a and 1243 a thatinclude, for example, an auto level switch that activates a circuit tolevel the fire truck using the stabilizer jacks and an override switchthat overrides circuits for emergency operation. The interface modules1225 and 1231 may also receive inputs from an operator panel such as astabilizer control panel 1242 b, which includes switches that controlthe raising and lowering of front and rear stabilizer jacks, and theextending and retracting of front and rear stabilizer jacks. Thestabilizer is an outrigger system which is deployed to prevent the firetruck from becoming unstable due to the deployment of an aerial system(e.g., an eighty-five foot extendable ladder). The interface module 1231may drive outputs that are used to control deployment the stabilizer,which can be deployed anywhere between zero and five feet.

The interface modules 1226 and 1232 are located near a turn table 1218at the rear of the fire truck 10. The interface modules may receiveinputs from switches and sensors 1244 a and 1245 a, as well as switchesthat are part of an aerial control panel 1245 b and are used to controlthe extension/retraction, raising/lowering, and rotation of the aerial1211. The interface modules 1226 and 1232 drive outputs that control theextension/retraction, raising/lowering, and rotation of the aerial 1211,as well as LED indicators 1254 b that provide operator feedbackregarding the positions of switches and other I/O status information.The interface modules 1227 and 1233 are located in the basket of theaerial and provide duplicate control for the extension/retraction,raising/lowering, and rotation of the aerial.

Additional inputs and outputs 1251 b may be used to establish acommunication link between the control system 12 and the control system1212. In other words, the digital on/off outputs of one control systemcan be connected to the switch inputs of the other control system, andvice versa. This provides for a mechanism of transferring I/O statusinformation back and forth between the two control systems 12 and 1212.

In another embodiment, the portion of the communication network thatconnects the interface modules 1227 and 1233 to the remainder of thecontrol system 1212 may be implemented using a wireless link. Thewireless link may be implemented by providing the interface modules 1227and 1233 with wireless RF communication interfaces such as a Bluetoothinterfaces. A wireless link may be advantageous in some instances inorder to eliminate maintenance associated with the network harness thatextends from the main vehicle body along the articulated arm formed bythe aerial 1211 to the interface modules 1227 and 1233. Also, given thatportions of the network harness can be positioned at significantdistances from the center of gravity of the vehicle 10, the use of awireless link is advantageous in that it reduces the weight of thearticulated arm, thereby enhancing the mechanical stability of thevehicle. In this regard, it may also be noted that it is possible toprovide all of the interface modules on the vehicle 10 with the abilityto communicate wirelessly with each other (e.g., using Bluetooth),thereby completely eliminating the need for a separate network harness.

The control system 1212 has complete motion control of the aerial 1211.To this end, the control program 1216 includes an envelope motioncontroller 1216 a, load motion controller 1216 b and interlockcontroller 1216 c. Envelope motion control refers to monitoring theposition of the aerial and preventing the aerial from colliding with theremainder of the fire truck 10, and otherwise preventing undesirableengagement of mechanical structures on the fire truck due to movement ofthe aerial. Envelope motion control is implemented based on the knowndimensions of the aerial 1211 and the known dimensions and position ofother fire truck structures relative to the aerial 1211 (e.g., theposition and size of the cab 17 relative to the aerial 1211) and theposition of the aerial 1211 (which is measured with feedback sensors1244 a and 1245 a). The control system 1212 then disallows inputs thatwould cause the undesirable engagement of the aerial 1211 with otherfire truck structures.

Load motion control refers to preventing the aerial from extending sofar that the fire truck tips over due to unbalanced loading. Load motioncontrol is implemented by using an appropriate sensor to measure thetorque placed on the cylinder that mechanically couples the aerial 1211to the remainder of the fire truck. Based on the torque and the knownweight of the fire truck, it is determined when the fire truck is closeto tipping, and warnings are provided to the operator by way of textmessages and LED indicators.

Interlock control refers to implementing interlocks for aerial systems.For example, an interlock may be provided that require the parking brakebe engaged before allowing the aerial to move, that require thestabilizers to be extended and set before moving the aerial 1211, thatrequire that the aerial PTO be engaged before attempting to move theaerial, and so on.

Advantageously, therefore, the control system makes the operation of theaerial much safer. For example, with respect to load motion control, thecontrol system 1212 automatically alerts firefighters if the extensionof the aerial is close to causing the fire truck to tip over. Factorssuch as the number and weight of people in the basket 1219, the amountand weight of equipment in the basket 1219, the extent to which thestabilizers are deployed, whether and to what extent water is flowingthrough aerial hoses, and so on, are taken into account automatically bythe torque sensors associated with the cylinder that mounts the aerialto the fire truck. This eliminates the need for a firefighter to have tomonitor these conditions manually, and makes it possible for the controlsystem 1212 to alert an aerial operator to unsafe conditions, and putsless reliance on the operator to make sure that the aerial is operatingunder safe conditions.

3. Alternative Control System Architecture

Referring now to FIG. 5, an architecture for an alternative controlsystem 1412 according to another preferred embodiment of the inventionis illustrated. By way of overview, the control system 1412 comprises aplurality of microprocessor-based interface modules 1420, a plurality ofinput and output devices 1440 and 1450 (see FIG. 6) that are connectedto the interface modules 1420, and a communication network 1460 thatinterconnects the interface modules 1420. The control system 1412 isgenerally similar to the control system 12, but includes severalenhancements. The control system 1412 preferably operates in the samemanner as the control system 12 except to the extent that differencesare outlined are below.

The interface modules 1420 are constructed in generally the same manneras the interface modules 20 and 30 and each include a plurality ofanalog and digital inputs and outputs. The number and type of inputs andoutputs may be the same, for example, as the vehicle interface modules30. Preferably, as described in greater detail below, only a single typeof interface module is utilized in order to increase the fieldserviceability of the control system 1412. Herein, the reference numeral1420 is used to refer to the interface modules 1420 collectively,whereas the reference numerals 1421–1430 are used to refer to specificones of the interface modules 1420. The interface modules are describedin greater detail in connection with FIGS. 6–8.

Also connected to the communication network 1460 are a plurality ofdisplays 1481 and 1482 and a data logger 1485. The displays 1481 and1482 permit any of the data collected by the control system 1412 to bedisplayed in real time, and also display warning messages. The displays1481 and 1482 also include membrane pushbuttons that allow the operatorsto scroll through, page through, or otherwise view the screens of datathat are available. The membrane pushbuttons may also allow operators tochange values of parameters in the control system 1412. The data logger1485 is used to store information regarding the operation of the vehicle1410. The data logger 1485 may also be used as a “black box recorder” tostore information logged during a predetermined amount of time (e.g.,thirty seconds) immediately prior to the occurrence of one or moretrigger events (e.g., events indicating that the vehicle 1410 has beendamaged or rendered inoperative, such as when an operational parametersuch as an accelerometer threshold has been exceeded).

Finally, FIG. 5 shows an engine system including an engine 1492 and anengine control system 1491, a transmission system including atransmission 1493 and a transmission control system 1494, and ananti-lock brake system including an anti-lock brake control system 1495.These systems may be interconnected with the control system 1412 ingenerally the same manner as discussed above in connection with theengine 92, the engine control system 91, the transmission 93, thetransmission control system 94, and the anti-lock brake system 36 ofFIG. 1.

Referring now also to FIGS. 6–8, the structure and interconnection ofthe interface modules 1420 is described in greater detail. Referringfirst to FIG. 6, the interconnection of the interface modules 1420 witha power source 1500 is described. The interface modules 1420 receivepower from the power source 1500 by way of a power transmission link1502. The interface modules 1420 are distributed throughout the vehicle1410, with some of the interface modules 1420 being located on thechassis 1417 and some of the interface modules 1420 being located on avariant module 1413. The variant module 1413 may be a module that isremovable/replaceable to provide the vehicle 1410 with different typesof functionality.

The control system is subdivided into three control systems including achassis control system 1511, a variant control system 1512, and anauxiliary control system 1513. The chassis control system 1511 includesthe interface modules 1421–1425 and the I/O devices 1441 and 1451, whichare all mounted on the chassis 1417. The variant control system 1512includes the interface modules 1426–1428 and the I/O devices 1442 and1452, which are all mounted on the variant module 1413. The auxiliarycontrol system 1513 includes the interface modules 1429–1430 and the I/Odevices 1443 and 1453, which may be mounted on either the chassis 1417or the variant module 1413 or both.

The auxiliary control system 1513 may, for example, be used to control asubsystem that is disposed on the variant module but that is likely tobe the same or similar for all variant modules (e.g., a lightingsubsystem that includes headlights, tail lights, brake lights, andblinkers). The inclusion of interface modules 1420 within a particularcontrol system may also be performed based on location rather thanfunctionality. For example, if the variant module 1413 has an aerialdevice, it may be desirable to have one control system for the chassis,one control system for the aerial device, and one control system for theremainder of the variant module. Additionally, although each interfacemodule 1420 is shown as being associated with only one of the controlsystems 1511–1513, it is possible to have interface modules that areassociated with more than one control system. It should also be notedthat the number of sub-control systems, as well as the number ofinterface modules, is likely to vary depending on the application. Forexample, a mobile command vehicle is likely to have more controlsubsystems than a wrecker variant, given the large number of I/O devicesusually found on mobile command vehicles.

The power transmission link 1502 may comprise a single power line thatis routed throughout the vehicle 1410 to each of the interface modules1420, but preferably comprises redundant power lines. Again, in order tominimize wiring, the interface modules 1420 are placed so as to belocated as closely as possible to the input devices 1440 from whichinput status information is received and the output devices 1450 thatare controlled. This arrangement allows the previously-describedadvantages associated with distributed data collection and powerdistribution to be achieved. Dedicated communication links, which mayfor example be electric or photonic links, connect the interface modules1421–1430 modules with respective ones of the I/O devices, as previouslydescribed.

Referring next to FIG. 7, the interconnection of the interface modules1420 by way of the communication network 1460 is illustrated. Aspreviously indicated, the control system 1412 is subdivided into threecontrol systems 1511, 1512 and 1513. In accordance with thisarrangement, the communication network 1460 is likewise furthersubdivided into three communication networks 1661, 1662, and 1663. Thecommunication network 1661 is associated with the chassis control system1511 and interconnects the interface modules 1421–1425. Thecommunication network 1662 is associated with the variant control system1512 and interconnects the interface modules 1426–1428. Thecommunication network 1663 is associated with the auxiliary controlsystem 1513 and interconnects the interface modules 1429–1430.Communication between the control systems 1511–1513 occurs by way ofinterface modules that are connected to multiple ones of the networks1661–1663. Advantageously, this arrangement also allows the interfacemodules to reconfigure themselves to communicate over another network inthe event that part or all of their primary network is lost.

In practice, each of the communication networks 1661–1663 may be formedof two or more communication networks to provide redundancy within eachcontrol system. Indeed, the connection of the various interface modules1420 with different networks can be as complicated as necessary toobtain the desired level of redundancy. For simplicity, these potentialadditional levels of redundancy will be ignored in the discussion ofFIG. 7 contained herein.

The communication networks 1661–1663 may be implemented in accordancewith SAE J1708/1587 and/or J1939 standards, or some other networkprotocol, as previously described. The transmission medium is preferablyfiber optic cable for robustness.

When the variant module 1413 is mounted on the chassis 1417, connectingthe chassis control system 1511 and the variant control system 1512 isachieved simply through the use of two mating connectors 1681 and 1682that include connections for one or more communication busses, power andground. The chassis connector 1682 is also physically and functionallymateable with connectors for other variant modules, i.e., the chassisconnector and the other variant connectors are not only capable ofmating physically, but the mating also produces a workable vehiclesystem. A given set of switches or other control devices 1651 on thedash (see FIG. 5) may then operate differently depending on whichvariant is connected to the chassis. Advantageously, therefore, it ispossible to provide a single interface between the chassis and thevariant module (although multiple interfaces may also be provided forredundancy). This avoids the need for a separate connector on thechassis for each different type of variant module, along with theadditional unutilized hardware and wiring, as has conventionally beenthe approach utilized.

Upon power up, the variant control system 1512 and the chassis controlsystem 1511 exchange information that is of interest to each other. Forexample, the variant control system 1512 may communicate the varianttype of the variant module 1413. Other parameters may also becommunicated. For example, information about the weight distribution onthe variant module 1413 may be passed along to the chassis controlsystem 1511, so that the transmission shift schedule of the transmission1493 can be adjusted in accordance with the weight of the variant module1413, and so that a central tire inflation system can control theinflation of tires as a function of the weight distribution of thevariant. Similarly, information about the chassis can be passed along tothe variant. For example, where a variant module is capable of beingused by multiple chassis with different engine sizes, engine informationcan be communicated to a wrecker variant module so that the wreckervariant knows how much weight the chassis is capable of pulling. Thus,an initial exchange of information in this manner allows the operationof the chassis control system 1511 to be optimized in accordance withparameters of the variant module 1413, and vice versa.

Referring next to FIG. 8, an exemplary one of the interface modules 1420is shown in greater detail. The interface modules 1420 each include amicroprocessor 1815 that is sufficiently powerful to allow eachinterface module to serve as a central control unit. The interfacemodules are identically programmed and each include a memory 1831 thatfurther includes a program memory 1832 and a data memory 1834. Theprogram memory 1832 includes BIOS (basic input/output system) firmware1836, an operating system 1838, and application programs 1840, 1842 and1844. The application programs include a chassis control program 1840,one or more variant control programs 1842, and an auxiliary controlprogram 1844. The data memory 1834 includes configuration information1846 and I/O status information 1848 for all of the modules 1420–1430associated with the chassis 1417 and its variant module 1413, as well asconfiguration information for the interface modules (N+1 to Z in FIG. 8)of other variant modules that are capable of being mounted to thechassis 1417.

It is therefore seen that all of the interface modules 1420 that areused on the chassis 1417 and its variant module 1413, as well as theinterface modules 1420 of other variant modules that are capable ofbeing mounted to the chassis 1417, are identically programmed andcontain the same information. Each interface module 1420 then utilizesits network address to decide when booting up which configurationinformation to utilize when configuring itself, and which portions ofthe application programs 1840–1844 to execute given its status as amaster or non-master member of one of the control systems 1511–1513. Amaster interface module may be used to provide a nexus for interfaceoperations with devices external to the control systems 1511–1513. Theinterface modules are both physically and functionally interchangeablebecause the interface modules are capable of being plugged in at anyslot on the network, and are capable of performing any functions thatare required at that slot on the network.

This arrangement is highly advantageous. Because all of the interfacemodules 1420 are identically programmed and store the same information,the interface modules are physically and functionally interchangeablewithin a given class of vehicles. The use of a single type of interfacemodule makes it easier to find replacement interface modules andtherefore enhances the field serviceability of the control system 1412.

Additionally, as previously noted, each interface module 1420 stores I/Ostatus information for all of the modules 1420–1430 associated with thechassis 1417 and its variant module 1413. Therefore, each interfacemodule 1420 has total system awareness. As a result, it is possible tohave each interface module 1420 process its own inputs and outputs basedon the I/O status information in order to increase system responsivenessand in order to reduce the amount of communication that is required withthe central control unit. The main management responsibility of thecentral control unit or master interface module above and beyond theresponsibilities of all the other interface modules 1420 then becomes,for example, to provide a nexus for interface operations with devicesthat are external to the control system of which the central controlunit is a part.

Referring now to FIGS. 9–12, a preferred technique for transmitting I/Ostatus information between the interface modules 1420 will now bedescribed. Although this technique is primarily described in connectionwith the chassis control system 1511, this technique is preferably alsoapplied to the variant control system 1512 and the auxiliary controlsystem 1513, and/or in the control system 12.

Referring first to FIG. 9, as previously described, the chassis controlsystem 1511 includes the interface modules 1421–1425, the input devices1441, and the output devices 1451. Also shown in FIG. 9 are the display1481, the data logger 1485, and the communication network 1661 whichconnects the interface modules 1421–1425. In practice, the system mayinclude additional devices, such as a plurality of switch interfacemodules connected to additional I/O devices, which for simplicity arenot shown. The switch interface modules may be the same as the switchinterface modules 20 previously described and, for example, may beprovided in the form of a separate enclosed unit or in the more simpleform of a circuit board mounted with associated switches and low poweroutput devices. In practice, the system may include other systems, suchas a display interface used to drive one or more analog displays (suchas gauges) using data received from the communication network 1661. Anyadditional modules that interface with I/O devices preferably broadcastand receive I/O status information and exert local control in the samemanner as detailed below in connection with the interface modules1421–1425. As previously noted, one or more additional communicationnetworks may also be included which are preferably implemented inaccordance with SAE J1708/1587 and/or J1939 standards. The communicationnetworks may be used, for example, to receive I/O status informationfrom other vehicle systems, such as an engine or transmission controlsystem. Arbitration of I/O status broadcasts between the communicationnetworks can be performed by one of the interface modules 1420.

To facilitate description, the input devices 1441 and the output devices1451 have been further subdivided and more specifically labeled in FIG.9. Thus, the subset of the input devices 1441 which are connected to theinterface module 1421 are collectively labeled with the referencenumeral 1541 and are individually labeled as having respective inputstates I-11 to I-15. Similarly, the subset of the output devices 1451which are connected to the interface module 1421 are collectivelylabeled with the reference numeral 1551 and are individually labeled ashaving respective output states O-11 to O-15. A similar pattern has beenfollowed for the interface modules 1422–1425, as summarized in Table Ibelow:

TABLE I Interface Input Input Output Output Module Devices StatesDevices States 1421 1541 I-11 to I-15 1551 O-11 to O-15 1422 1542 I-21to I-25 1552 O-21 to O-25 1423 1543 I-31 to I-35 1553 O-31 to O-35 14241544 I-41 to I-45 1554 O-41 to O-45 1425 1545 I-51 to I-55 1555 O-51 toO-55

Of course, although five input devices 1441 and five output devices 1451are connected to each of the interface modules 1420 in the illustratedembodiment, this number of I/O devices is merely exemplary and adifferent number of devices could also be used, as previously described.

The interface modules 1420 each comprise a respective I/O status table1520 that stores information pertaining to the I/O states of the inputand output devices 1441 and 1451. Referring now to FIG. 10, an exemplaryone of the I/O status tables 1520 is shown. As shown in FIG. 10, the I/Ostatus table 1520 stores I/O status information pertaining to each ofthe input states I-11 to I-15, I-21 to I-25, I-31 to I-35, I-41 to I-45,and I-51 to I-55 of the input devices 1541–1545, respectively, and alsostores I/O status information pertaining to each of the output statesO-11 to O-15, O-21 to O-25, O-31 to O-35, O-41 to O-45, and O-51 to O-55of the output devices 1551–1555, respectively. The I/O status tables1520 are assumed to be identical, however, each I/O status table 1520 isindividually maintained and updated by the corresponding interfacemodule 1420. Therefore, temporary differences may exist between the I/Ostatus tables 1520 as updated I/O status information is received andstored. Although not shown, the I/O status table 1520 also stores I/Ostatus information for the interface modules 1426–1428 of the variantcontrol system 1512 and the interface modules 1429–1430 of the auxiliarycontrol system 1513.

In practice, although FIG. 10 shows the I/O status information beingstored next to each other, the memory locations that store the I/Ostatus information need not be contiguous and need not be located in thesame physical media. It may also be noted that the I/O status table 1520is, in practice, implemented such that different I/O states are storedusing different amounts of memory. For example, some locations store asingle bit of information (as in the case of a digital input device ordigital output device) and other locations store multiple bits ofinformation (as in the case of an analog input device or an analogoutput device). The manner in which the I/O status table is implementedis dependent on the programming language used and on the different datastructures available within the programming language that is used. Ingeneral, the term I/O status table is broadly used herein to encompassany group of memory locations that are useable for storing I/O statusinformation.

Also shown in FIG. 10 are a plurality of locations that storeintermediate status information, labeled IM-11, IM-21, IM-22, and IM-41.The intermediate states IM-11, IM-21, IM-22, and IM-41 are processedversions of selected I/O states. For example, input signals may beprocessed for purposes of scaling, unit conversion and/or calibration,and it may be useful in some cases to store the processed I/O statusinformation. Alternatively, the intermediate states IM-11, IM-21, IM-22,and IM-41 may be a function of a plurality of I/O states that incombination have some particular significance. The processed I/O statusinformation is then transmitted to the remaining interface modules 1420.

Referring now to FIGS. 11–12, FIG. 11 is a flowchart describing theoperation of the control system of FIG. 9, and FIG. 12 is a data flowdiagram describing data flow through an exemplary interface moduleduring the process of FIG. 11. As an initial matter, it should be notedthat although FIG. 11 depicts a series of steps which are performedsequentially, the steps shown in FIG. 11 need not be performed in anyparticular order. In practice, for example, modular programmingtechniques are used and therefore some of the steps are performedessentially simultaneously. Additionally, it may be noted that the stepsshown in FIG. 11 are performed repetitively during the operation of theinterface module 1421, and some of the steps are in practice performedmore frequently than others. For example, input information is acquiredfrom the input devices more often than the input information isbroadcast over the communication network. Although the process of FIG.11 and the data flow diagram of FIG. 12 are primarily described inconnection with the interface module 1421, the remaining interfacemodules 1422–1425 operate in the same manner.

At step 1852, the interface module 1421 acquires input statusinformation from the local input devices 1541. The input statusinformation, which pertains to the input states I-11 to I-15 of theinput devices 1541, is transmitted from the input devices 1541 to theinterface module 1421 by way of respective dedicated communicationlinks. At step 1854, the input status information acquired from thelocal input devices 1541 is stored in the I/O status table 1520 at alocation 1531. For the interface module 1421, the I/O devices 1541 and1551 are referred to as local I/O devices since the I/O devices 1541 and1551 are directly coupled to the interface module 1421 by way ofrespective dedicated communication links, as opposed to the remainingnon-local I/O devices and 1542–1545 and 1552–1555 which are indirectlycoupled to the interface module 1421 by way of the communication network1661.

At step 1856, the interface module 1421 acquires I/O status informationfor the non-local input devices 1542–1545 and the non-local outputdevices 1552–1555 by way of the communication network 1661.Specifically, the interface module 1421 acquires input statusinformation pertaining to the input states I-21 to I-25, I-31 to I-35,I-41 to I-45, I-51 to I-55 of the input devices 1542–1545, respectively,and acquires output status information pertaining to the output statesO-21 to O-25, O-31 to O-35, O-41 to O-45, O-51 to O-55 of the outputdevices 1552–1555. The input status information and the output statusinformation are stored in locations 1533 and 1534 of the I/O statustable 1520, respectively.

At step 1860, the interface module 1421 determines desired output statesO-11 to O-15 for the output devices 1551. As previously noted, each ofthe interface modules 1420 stores a chassis control program 1840, one ormore variant control programs 1842, and an auxiliary control program1844. The interface module 1421 is associated with the chassis controlsystem 1511 and, therefore, executes a portion of the chassis controlprogram 1840. (The portion of the chassis control program 1840 executedby the interface module 1421 is determined by the location of theinterface module 1421 on the vehicle 1410, as previously described.) Theinterface module 1421 executes the chassis control program 1840 todetermine the desired output states O-11 to O-15 based on the I/O statusinformation stored in the I/O status table 1520. Preferably, eachinterface module 1420 has complete control of its local output devices1450, such that only I/O status information is transmitted on thecommunication network 1460 between the interface modules 1420.

At step 1862, the interface module 1421 controls the output devices 1551in accordance with the desired respective output states O-11 to O-15.Once the desired output state for a particular output device 1551 hasbeen determined, control is achieved by transmitting a control signal tothe particular output device 1551 by way of a dedicated communicationlink. For example, if the output is a digital output device (e.g., aheadlight controlled in on/off fashion), then the control signal isprovided by providing power to the headlight by way of the dedicatedcommunication link. Ordinarily, the actual output state and the desiredoutput state for a particular output device are the same, especially inthe case of digital output devices. However, this is not always thecase. For example, if the headlight mentioned above is burned out, theactual output state of the headlight may be “off,” even though thedesired output state of the light is “on.” Alternatively, for an analogoutput device, the desired and actual output states may be different ifthe control signal is not properly calibrated for the output device.

At step 1864, the interface module 1421 stores output status informationpertaining to the desired output states O-11 to O-15 for the outputdevices 1551 in the I/O status table 1520. This allows the output statesO-11 to O-15 to be stored prior to being broadcast on the communicationnetwork 1661. At step 1866, the interface module 1421 broadcasts theinput status information pertaining to the input states I-11 to I-11 ofthe input devices 1541 and the output status information pertaining tothe output states O-11 to O-15 of the output devices 1551 over thecommunication network 1661. The I/O status information is received bythe interface modules 1422–1425. Step 1866 is essentially the oppositeof step 1856, in which non-local I/O status information is acquired bythe interface module 1421 by way of the communication network 1661. Inother words, each interface module 1420 broadcasts its portion of theI/O status table 1520 on the communication network 1661, and monitorsthe communication network 1661 for broadcasts from the remaininginterface modules 1420 to update the I/O status table 1520 to reflectupdated I/O states for the non-local I/O devices 1441 and 1451. In thisway, each interface module 1420 is able to maintain a complete copy ofthe I/O status information for all of the I/O devices 1441 and 1451 inthe system.

The interface modules 1423 and 1425 are used to transmit I/O statusinformation between the various control systems 1511–1513. Specifically,as previously noted, the interface module 1423 is connected to both thecommunication network 1661 for the chassis control system 1511 and tothe communication network 1662 for the variant control system 1512. Theinterface module 1423 is preferably utilized to relay broadcasts of I/Ostatus information back and forth between the interface modules1421–1425 of the chassis control system 1511 and the interface modules1426–1428 of the variant control system 1512. Similarly, the interfacemodule 1425 is connected to both the communication network 1661 for thechassis control system 1511 and the to the communication network 1663for the auxiliary control system 1513, and the interface module 1425 ispreferably utilized to relay broadcasts of I/O status information backand forth between the interface modules 1421–1425 of the chassis controlsystem 1511 and the interface modules 1429–1430 of the auxiliary controlsystem 1513.

The arrangement of FIGS. 9–12 is advantageous because it provides a fastand efficient mechanism for updating the I/O status information 1848stored in the data memory 1834 of each of the interface modules 1420.Each interface module 1420 automatically receives, at regular intervals,complete I/O status updates from each of the remaining interface modules1420. There is no need to transmit data request (polling) messages anddata response messages (both of which require communication overhead) tocommunicate information pertaining to individual I/O states betweenindividual I/O modules 1420. Although more I/O status data istransmitted, the transmissions require less overhead and therefore theoverall communication bandwidth required is reduced.

This arrangement also increases system responsiveness. First, systemresponsiveness is improved because each interface module 1420 receivescurrent I/O status information automatically, before the information isactually needed. When it is determined that a particular piece of I/Ostatus information is needed, there is no need to request thatinformation from another interface module 1420 and subsequently wait forthe information to arrive via the communication network 1661. The mostcurrent I/O status information is already assumed to be stored in thelocal I/O status table 1520. Additionally, because the most recent I/Ostatus information is always available, there is no need to make apreliminary determination whether a particular piece of I/O statusinformation should be acquired. Boolean control laws or other controllaws are applied in a small number of steps based on the I/O statusinformation already stored in the I/O status table 1520. Conditionalcontrol loops designed to avoid unnecessarily acquiring I/O statusinformation are avoided and, therefore, processing time is reduced.

It may also be noted that, according to this arrangement, there is noneed to synchronize the broadcasts of the interface modules 1420. Eachinterface module 1420 monitors the communication network 1661 todetermine if the communication network 1661 is available and, if so,then the interface module broadcasts the I/O status information forlocal I/O devices 1441 and 1451. (Standard automotive communicationprotocols such as SAE J1708 or J1939 provide the ability for each memberof the network to monitor the network and broadcast when the network isavailable.) Although it is desirable that the interface modulesrebroadcast I/O status information at predetermined minimum intervals,the broadcasts may occur asynchronously.

The technique described in connection with FIGS. 9–12 also provides aneffective mechanism for detecting that an interface module 1420 hasbecome inoperable. As just noted, the interface modules 1420 rebroadcastI/O status information at predetermined minimum intervals. Eachinterface module 1420 also monitors the amount of time elapsed since anupdate was received from each remaining interface module 1420.Therefore, when a particular interface module 1420 has becomeinoperable, the inoperability of the interface module 1420 can bedetected by detecting the failure of the interface module 1420 torebroadcast its I/O status information within a predetermined amount oftime. Preferably, the elapsed time required for a particular interfacemodule 1420 to be considered inoperable is several times the expectedminimum rebroadcast time, so that each interface module 1420 is alloweda certain number of missed broadcasts before the interface module 1420is considered inoperable. A particular interface module 1420 may beoperable and may broadcast I/O status information, but the broadcast maynot be received by the remaining interface modules 1420 due, forexample, to noise on the communication network.

This arrangement also simplifies the operation of the data logger 1485and automatically permits the data logger 1485 to store I/O statusinformation for the entire control system 1412. The data logger 1485monitors the communication network 1661 for I/O status broadcasts in thesame way as the interface modules 1420. Therefore, the data logger 1485automatically receives complete system updates and is able to storethese updates for later use.

As previously noted, in the preferred embodiment, the interface modules1423 and 1425 are used to transmit I/O status information between thevarious control systems 1511–1513. In an alternative arrangement, theinterface module 1429 which is connected to all three of thecommunication networks 1661–1663 could be utilized instead. Althoughless preferred, the interface module 1429 may be utilized to receive I/Ostatus information from each of the interface modules 1421–1428 and1430, assemble the I/O status data into an updated I/O status table, andthen rebroadcast the entire updated I/O status table 1520 to each of theremaining interface modules 1421–1428 and 1430 at periodic or aperiodicintervals. Therefore, in this embodiment, I/O status information for theall of the interface modules 1420 is routed through the interface module1429 and the interface modules 1420 acquire I/O status information fornon-local I/O devices 1440 and 1450 by way of the interface module 1429rather than directly from the remaining interface modules 1420.

4. Additional Aspects

The preferred control systems and methods exhibit enhanced reliabilityand maintainability because it uses distributed power distribution anddata collecting. The interface modules are interconnected by a networkcommunication link instead of a hardwired link, thereby reducing theamount of wiring on the fire truck. Most wiring is localized wiringbetween the I/O devices and a particular interface module.

Additionally, the interface modules in the preferred systems areinterchangeable units. If the control system were also applied to othertypes of equipment service vehicles (e.g., snow removal vehicles, refusehandling vehicles, cement/concrete mixers, military vehicles such asthose of the multipurpose modular type, on/off road severe dutyequipment service vehicles, and so on), the interface modules would evenbe made interchangeable across platforms since each interface moduleviews the outside world in terms of generic inputs and outputs.

B. Turret Control

Referring to FIGS. 13–16, a turret 610 that is controlled by a firefighting vehicle control system 612 according to another embodiment ofthe invention is illustrated. The turret control system 612 may beimplemented as a stand-alone system or in combination with one of thecontrol system architectures described above. Except as specificallynoted, the following discussion is generally applicable to both types ofembodiments.

Referring first to FIG. 13, FIG. 13 is an overview of the preferredcontrol system 612 for controlling the turret 610. The control system612 includes a plurality of interface modules 613 a–613 d (collectively,“the interface modules 613”), turret I/O devices 614, and one or moreoperator interfaces 616 a and 616 b (collectively, “the operatorinterfaces 616”). The control system 612 may be implemented using theinterface modules 613 regardless whether the control system 612 isimplemented in combination with the control system 12. If the controlsystem 612 is implemented in combination with the control system 12,then other, non-turret I/O devices may also be coupled to the interfacemodules 613. If the control system 612 is implemented as a stand-alonecontrol system, then it may be preferable to replace the interfacemodules 613 with a single stand-alone electronic control unit.

As discussed in greater detail in connection with FIGS. 14–15, theturret I/O devices 614 include actuators, position sensors, limitswitches and other devices used to control the turret 610. The operatorinterfaces 616 a and 616 b each include display 618 a and 618 b(collectively, “the displays 618”) and joysticks 619 a and 619 b(collectively, “the joysticks 619”). For example, the operator interface616 a may be located in a driver compartment of the fire fightingvehicle 620 and the other operator interface 616 b may be located atanother location, such as a rear or side vehicle location of the firefighting vehicle 620, for example.

Assuming the control system 612 is implemented in combination with thecontrol system 12 (with or without the enhancements of FIGS. 5–12), theinterface modules 613 are connected to each other by way of thecommunication network 60, previously described in connection with FIGS.1–4. Therefore, the interface modules shown in FIG. 13 are coupled tothe same communication network 60 as the interface modules shown inFIGS. 1–4. For simplicity, in describing the turret control system 612,all of the interface modules in the turret control system 612 as well asthe interface modules shown in FIGS. 1–4 will be referred to using thereference number 613. As previously described, the interface modules 613are locally disposed with respect to the respective input and outputdevices to which each interface module is coupled so as to permitdistributed data collection from the plurality of input devices anddistributed power distribution to the plurality of output devices. Ofcourse, each of the interface modules 613 may, in addition, be coupledto other non-local input devices and output devices. Further, thecontrol system 612 can also include input devices and output deviceswhich are not connected to the interface modules 613.

It may also be noted that if the control system 12 is employed, it ispreferably implemented so as to incorporate the additional featuresdescribed in connection with FIGS. 5–12. Therefore, all of the interfacemodules 613 are preferably identically constructed and programmed.Further, each of the interface modules 613 broadcasts I/O statusinformation on the communication network 60, and each of the interfacemodules 613 uses the I/O status broadcasts to maintain an I/O statustable 1520. Based on the I/O status information stored in the I/O statustable 1520 maintained by each respective interface module 613, therespective interface module 613 executes pertinent portions of thecontrol programs to control the output devices to which it is directlyconnected. It may also be noted that the fire fighting vehicle 620 maybe implemented as an electric vehicle, as described in connection withFIGS. 25–33 of U.S. Prov. No. 60/360,479 and U.S. Ser. No. 10/326,907,and/or include the network assisted scene management features of FIGS.34–41 of U.S. Prov. No. 60/360,479 and U.S. Ser. No. 10/326,907, and/orbe implemented to include the network-assisted monitoring, serviceand/or repair features described in connection with FIGS. 42–67 of U.S.Prov. No. 60/360,479 and U.S. Ser. No. 10/326,907.

Referring now also to FIG. 14, FIG. 14 shows one embodiment of theturret 610, although it should be noted that the teachings herein do notdepend on the exact configuration, construction, size or assembly of theturret 610. In this regard, it will be appreciated that the turret 610is not necessarily drawn to scale in FIG. 14 relative to the firefighting vehicle 620.

The turret 610 is shown to be of a type used on fire fighting vehiclessuch as municipal and airport fire trucks, crash trucks, emergencyresponse vehicles, aerial platform trucks, ladder trucks, pumpers,tankers, and so on. Generally, such vehicles have a chassis and avehicle body mounted on the chassis, with the chassis and vehicle bodyin combination including an operator compartment capable of receiving ahuman operator. The operator compartment further includes steering andthrottle controls for receiving operator inputs to control movement ofthe fire fighting vehicle along a road. The turret 610 is mounted to aroof of the fire fighting vehicle 620, and is configured to deploy ordispense a fire fighting agent (i.e., water, foam, foaming agents,etc.). It should be understood that FIG. 15 merely illustrates oneembodiment, and the turret 610 may be mounted anywhere and in any mannerto the chassis/vehicle body of the fire fighting vehicle 620.

The turret 610 includes an adjustable mount assembly which includes afire-extinguishing agent delivery system capable of transporting afire-extinguishing agent through the mount assembly. In one embodiment,the adjustable mount assembly comprises a base 624, a first arm 626, asecond arm 628, a third arm 630, and a nozzle 631. The arms 626–630 arehingedly moveable relative to each other and, in combination, form aboom for placing the nozzle 631 in a particular position andorientation. As will be appreciated, the arms 624–626 are not drawn toscale, and may have lengths which are significantly larger than thoseshown relative to the overall size of the fire fighting vehicle 620.Also, although three arms are shown which are movable in particulardirections, fewer or more arms may be used which may be moveable in adifferent manner.

The base 624 is preferably configured to mount to the top of the firefighting vehicle 620. In one embodiment, the base 624 is configured toswivel or rotate around an axis, as indicated by θ1. In anotherembodiment, the base 624 is fixed and is not able to rotate. Assumingthat the base 624 is configured to rotate, and referring now also toFIG. 15, the base 624 may be coupled to a motor or other actuator (shownas actuator 632 a) which causes the rotation of the base 624 in thedirection of θ1. A position indicator or sensor 634 a measures movementof the base 624 in the θ1 direction, and a pair of limit switches 636 aascertain whether the base 624 is at one of the boundaries of movementin the θ1 direction.

The first arm 626 is rotatably coupled to the base 624, and is mountedfor hinged movement, as indicated by θ2. The first arm 626 may becoupled to a motor or other actuator (shown as actuator 632 b) whichcauses the rotation of the first arm 626 around θ2. A position sensor634 b measures movement of the first arm 626 in the θ2 direction, and apair of limit switches 636 b ascertain whether the first arm 626 is atone of the boundaries of movement in the θ2 direction.

The second arm 628 is rotatably coupled to the first arm 626 and ismounted for hinged movement, as indicated by θ3. The second arm 628 maybe coupled to a motor or other actuator (shown as actuator 632 c) whichcauses the rotation of the second arm 628 around θ3. A position sensor634 c measures movement of the second arm 628 in the θ3 direction, and apair of limit switches 636 c ascertain whether the second arm 628 is atthe one of the boundaries of movement in the θ3 direction.

The second arm 628 may also have a length which is adjustable (i.e.,extendable or retractable) as indicated by L1. The second arm 628 mayfurther be coupled to a motor or other actuator (shown as actuator 632d) which causes the extension of the second arm 628 along L1.Adjustments along L1 allow for changes in the height of the turret 610without requiring the rotation of any arm. A position sensor 634 dmeasures movement of the second arm 628 in the L1 direction, and a pairof limit switches 636 d ascertain whether the second arm 628 is at oneof the boundaries of movement in the L1 direction.

The third arm 630 is rotatably coupled to the second arm 628, and ismounted for hinged movement, as indicated by θ4. The third arm 630 maybe coupled to a motor or other actuator (shown as actuator 632 e) whichcauses the rotation of the third arm 630 around θ4. A position sensor634 e measures movement of the third arm 630 in the θ4 direction, and apair of limit switches 636 e ascertain whether the third arm 630 is atthe one of the boundaries of movement in the θ4 direction.

The third arm 630 may also swivel around a vertical axis, as indicatedby θ5. The third arm 630 may further be coupled to a motor or otheractuator (shown as actuator 632 f) which causes the rotation of thethird arm 630 around θ5. A position sensor 634 f measures movement ofthe third arm 630 in the θ5 direction, and a pair of limit switches 636f ascertain whether the third arm 630 is at the one of the boundaries ofmovement in the θ5 direction.

The base 624, the first arm 626, the second arm 628, and the third arm630 are fluidly connected, allowing the flow of a fire fighting agent topass from the base 624 to the third arm 630. Fire fighting agent entersthe base 624 from a source such as a pump, hydrant, pipe, etc. Thenozzle 631 is mounted on a free end of the third arm 630 and receivesthe fire-extinguishing agent transported by the arms 626–630. Theposition and orientation of the nozzle 631 are controlled by a turretcontroller 660 (discussed below in connection with FIG. 16) to directthe flow of fire fighting agent toward an intended target or otherregion of interest such as a fire, chemical spill, etc. Furthermore, thenozzle 631 may be capable of controlling the flow rate of fire fightingagent (as indicated by F1). The nozzle 631 may further be coupled to amotor or actuator (shown as actuator 632 g) which controls the flow ratesetting for the nozzle 631. A position or flow rate sensor 634 gmeasures the nozzle setting, and a set of switches or other sensors 636g provide information regarding whether the setting of the nozzle 631 isat particular levels (e.g., full on, full off). The flow rate sensor 634g may measure the flow rate at the nozzle 631, or may measure the amountof fire fighting agent remaining in an on-board storage tank and deduceflow rate by calculating the rate of change in the amount of remainingfire fighting agent.

In an exemplary embodiment, the turret 610 is a Snozzle Model C-50 or50A available from Crash Rescue Equipment Service, Inc. of Dallas, Tex.In an alternative embodiment, the turret 610 is a Snozzle Model P-50 or50A also available from Crash Rescue Equipment Service, Inc. of Dallas,Tex. In another alternative embodiment, the turret 610 may be a RhinoBumper Turret available from Crash Rescue Equipment Service, Inc. ofDallas, Tex. As previously indicated, however, the particularconfiguration of the turret is not important and other turret systemsfrom other manufacturers could also be used.

As shown in FIG. 15, the position indicators or sensors 634 a–634 g(collectively, “the position sensors 634”) and the limit switches 636a–636 g (collectively, “the limit switches 636”) are connected as inputdevices to the interface modules 613 a–613 b. The interface modules 613a–613 b thereby receive the position information pertaining to theposition and orientation of the nozzle 631. The actuators 632 a–632 g(collectively, “the actuators 632”) are connected as output devices tothe interface modules 613 a–613 b. The interface modules 613 a–613 bprovide the actuators 632 with control signals to adjust the base 624and the arms 626–630 to thereby adjust the position and orientation ofthe nozzle 631. The actuators 632, the position sensors 634 and thelimit switches 636 collectively correspond to “the turret I/O devices”which are labeled with the reference number 614 in FIG. 13. Other I/Odevices may also be used. The interface module 613 a may be located nearthe nozzle 631 of the turret 610 and the interface module 613 b may belocated near the base 624 of the turret 610, with the turret I/O devices614 preferably being connected to a particular interface module 613 a,613 b based on location.

In one embodiment, the portion of the communication network thatconnects the interface module 613 a to the remainder of the controlsystem 612 is implemented using a wireless link. The wireless link maybe implemented by providing the interface module 613 a with a wirelessRF communication interface such as a Bluetooth interface. A wirelesslink may be advantageous in some instances in order to eliminatemaintenance associated with a network harness that extends from the mainvehicle body along the articulated arms 626–630. Also, given thatportions of the network harness can be positioned at significantdistances from the center of gravity of the vehicle 620, the use of awireless link is advantageous in that it reduces the weight of thearticulated arm, thereby enhancing the mechanical stability of thevehicle 620. Again, it may also be noted that it is possible to provideall of the interface modules on the vehicle 620 with the ability tocommunicate wirelessly with each other (e.g., using Bluetooth), therebycompletely eliminating the need for a separate network harness.

The position sensors 634 may be encoders, resolvers or other suitableposition measuring devices. The actuators 632 may be electric motors,especially if the fire fighting vehicle is implemented as an electricvehicle (for example, the electric vehicle 1910 described in connectionwith FIGS. 25–33 of U.S. Prov. No. 60/360,479 and U.S. Ser. No.10/326,907). Alternatively, the actuators 632 may for example beelectrically controlled valves that control the flow of hydraulic powerto the turret if turret movement is hydraulically driven. Otherarrangements could also be used.

The joysticks 619 are preferably multi-axis joysticks, with the controlsystem 612 being capable of receiving operator inputs from eitherjoystick 619 a, 619 b and using the operator inputs to control theturret 610, as detailed below. In one embodiment, the joysticks arethree-axis joysticks, with left to right corresponding to boom up andboom down (θ2 and θ3 control), forward and back corresponding to nozzleup and nozzle down (θ4 control), and twist corresponding to nozzle leftand nozzle right (θ5 control). In this configuration, the base 624 isheld stationary. Additional or alternative operator input devices may beused if the base 624 is not held stationary, if the joysticks 619 areimplemented using two-axis joysticks rather than three-axis joysticks,or if a different type of operator input device is desired. In practice,the configuration of the joysticks may vary from system to systemdepending on user preferences. As described in greater detail below, inan alternative embodiment, the fire fighting vehicle 620 includes twoturrets, with each of the joysticks 619 a and 619 b being useable tocontrol either or both turrets, depending on how the turret controller660 is configured.

Because the joysticks 619 are coupled to the actuators 632 through theturret controller 660, the turret controller 660 can process theoperator inputs from the joysticks 619 to provide user-friendly controlof the actuators 632. For example, the turret controller 660 may beprogrammed to increase the speed of movement of the turret 610 as theoperator maintains a particular joystick position. For example, if theoperator holds the joystick 619 a or 619 b in the left position, thespeed of upward movement of the boom may be programmed to increase thelonger the joystick-left position is maintained.

Referring now to FIG. 16, the arrangement of FIGS. 13–15 can be used toimplement a variety of advantageous features, such as turret envelopecontrol, turret targeting, turret pan, turret deploy, turret store andother features. FIG. 16 is a block diagram of a turret control systemthat implements such features. The turret control system 612 comprisesthe operator interface 616, a turret motion controller 660, theactuators 632, the position sensors 634, and a plurality of other inputdevices such as a fire position indicator 635, described in greaterdetail below.

In the preferred embodiment, the turret motion controller 660 isimplemented using interface modules, and preferably comprises theinterface modules 613 a and 613 b of FIG. 13. According to thisarrangement, and as previously indicated, all of the interface modules613 are preferably identically programmed, and the interface modules 613each include control programs which implement a plurality of controlmodules 661 including an envelope control module 662, a turret targetingmodule 664, a turret learn module 665, a turret pan module 668, a turretdeploy module 670, and a turret store module 672. The interface module613 a then receives I/O status information from other interface modules613 through I/O status broadcasts, and maintains an I/O status table1520 based on the I/O status broadcasts and based on locallyacquired/determined I/O status information. The interface module 613 athen controls the actuators 632 a–632 d by executing those portions ofthe control programs pertinent to the actuators 632 a–632 d and usingthe I/O status information stored in its I/O status table 1520. Theinterface module 613 b operates in the same manner, except that itcontrols the actuators 632 g–632 f by executing those portions of thecontrol programs pertinent to the actuators 632 g–632 f. As a practicalmatter, there is a significant of overlap between the portions of thecontrol program pertinent to the actuators 632 a–632 d and the portionsof the control program pertinent to the actuators 632 e–632 g. Theinterface modules 613 c and 613 d are not shown in FIG. 16, although itis to be understood that the input information from the operatorinterfaces 616 is received by the interface modules 613 c and 613 d andtransmitted from the interface modules 613 c and 613 d to the interfacemodules 613 a and 613 b in the form of an I/O status broadcast over thecommunication network 60.

The envelope control, turret targeting, turret pan, turret deploy,turret store and other features will now be described in greater detail.

1. Envelope Control

As shown in FIG. 16, the motion controller 660 has an envelope controlmodule 662 that provides envelope control to improve turret guidance,safety, and crash avoidance. The motion controller 660 assists a humanturret operator who may have obscured vision from smoke, debris,buildings, etc, and who is susceptible to controlling the turret 610 soas to inadvertently cause the turret 610 to collide with an objectwithin the range of motion of the turret 610. Thus, as shown in FIG. 13,the turret 610 has a maximum overall range of motion (i.e., a limit orthe maximum extent which the turret can physically extend) shown as aboundary 615. Within the boundary 615 are obstructions that the turret610 is susceptible to impacting. The obstructions may include, forexample, portions of the vehicle 620. A permissible travel envelope 618,shown in FIG. 14, shows the three-dimensional space within the overallrange of motion which does not include the obstructions, and thereforewithin which the turret 610 may safely be positioned and move. It shouldbe noted that the shape of the range of motion as well as the envelope618 are shown only as examples, and that a wide variety of shapes,configurations, and arrangements may be used according to theseteachings. The control system 612 provides capabilities to identify thelocation of objects within the range of motion of the turret 610 (suchas the cab or chassis of the fire fighting vehicle, as well as otherobjects) to avoid collision with those objects.

In describing operation of the envelope control module 662, it isinitially assumed that the envelope control module 662 is used when ahuman operator is controlling the turret 610 using the operatorinterface 616 (although, as detailed below, the envelope control module662 is also useable when the turret 610 is under control of one of themodules 664, 668, 670, or 672). In this case, the modules 664, 665, 668,670, 672 and 674 and the fire position indicator 635 are not active.

The operation of the turret controller 660 and particularly the envelopecontrol module 662 is described in greater detail in connection with theflowcharts of FIGS. 17–19. Referring first to FIG. 17, at step 681,operator inputs are received from one of the operator interfaces 616 andtransmitted by the appropriate interface module 613 c or 613 d in theform of an I/O status broadcast to all of the interface modulesincluding the interface modules 613 a–613 b, which form the turretmotion controller 660. The turret motion controller 660 acquires theoperator inputs and processes (e.g., scales, amplifies, powerconditions, etc.) the inputs to generate control signals to controlmotion of the turret 610. As originally acquired, the operator inputsmay direct movement of the turret 610 in such a way that the turret 610is susceptible to impacting the fire fighting vehicle 620. The operatorinputs are also provided to the envelope control module 660 (theabove-mentioned processing may be performed before and/or after theoperator inputs are provided to the envelope control module 660).Schematically, a selector switch 675 is shown in FIG. 16 to indicatethat the envelope control module 662 uses inputs from one of theoperator interfaces 616 as opposed to inputs from one of the modules664, 668, 670, 672, but it will be understood that the selector switch675 is representative of logic that is implemented the control programexecuted by the turret motion controller 660.

At the same time, at step 682, the position of the actuators 632 ismonitored by the position sensors 634, and the current position of theactuators 632 is fed back to the envelope control module 662. At step683, the envelope control module 662 compares the current position ofthe turret 610 with a representation 671 of the permissible travelenvelope for the turret 610 and, at step 684, it is determined whetherthe turret 610 is near/past the edge of the envelope or is otherwisesusceptible to impacting the vehicle 620. Steps 683–84 are described ingreater detail below. At step 685, when the turret 610 is not near/pastthe edge of the envelope, the turret motion controller 660 operatesessentially as a pass-through device, and passes the inputs receivedfrom the joystick 619 a or 619 b along to the actuators 632 withoutintervention. Alternatively, at step 686, when the turret 610 is nearthe edge of the operating envelope, or is past the edge of the operatingenvelope (depending on how steps 683–84 are implemented, as describedbelow), the envelope control module 662 becomes active and provides theactuators 632 with different control signals to alter a path of travelof the turret 610, e.g., to prevent the turret 610 from travelingoutside the permissible travel envelope and thus prevent the turret 610from impacting the vehicle 620.

The specific manner of operation of the envelope control module 662 atsteps 683–84 depends in part on the scheme that is used to store therepresentation 671 of the permissible travel envelope. Therepresentation 671 may be a data set of positions, coordinates,positional/axis limits, boundaries, and so on. According to onepreferred embodiment, the representation 671 is stored in the form ofpermissible or impermissible combinations of values for the parametersθ1, θ2, θ3, θ4, θ5 and L1. Thus, the ranges of values of the parametersθ1, θ2, θ3, θ4, θ5 and L1 that would cause a portion of the turret 610to occupy the same space as part of the fire fighting vehicle 620, aswell as a buffer zone surrounding the fire fighting vehicle 620, aredetermined and stored to form the representation 671. For example, therepresentation may store limit information such that, when the turret610 is near the store position (the position where the turret 610 isstored during vehicle travel) as indicated by the θ1, θ2, θ3, and θ4values, the θ5 value must be approximately zero (i.e., the turret nozzle631 must not be angularly displaced to the left or the right) to avoidthe turret nozzle 631 colliding with other structure (e.g., emergencylights) on the roof of the fire fighting vehicle 620. The turret 610 maythen be controlled so as to avoid these combinations of values for theparameters θ1, θ2, θ3, θ4, θ5 and L1 and thereby avoid impacting thefire fighting vehicle 620.

According to another preferred embodiment, the representation 662 is adata set containing (X,Y,Z) coordinates that the turret maysafely/permissibly occupy or not occupy. Specifically, an XYZ vehiclecoordinate system is established for the fire fighting vehicle 620 withthe base 624 at the origin of the coordinate system (see FIG. 13). Theoverall range of motion of the turret 610 around the fire fightingvehicle 620 is determined based on the lengths and relative angles ofthe arms 626–630 of the turret 610. The space around the fire fightingvehicle 620 is then divided into volume elements, with each X,Y,Zcoordinate being located within a respective volume element. Therepresentation 671 is then constructed by defining which volume elementsare inside the permissible travel envelope and which volume elements areoutside the permissible travel envelope. Assuming initially that themain obstruction to be avoided is the fire fighting vehicle 620, thepermissible travel envelope may be defined (typically, in advance ofvehicle deployment) based on the known dimensions of the fire fightingvehicle 620 relative to the origin of the vehicle coordinate system.

Assuming the representation 671 is constructed in this manner, thenFIGS. 18–19 show exemplary techniques for performing steps 683–684 inFIG. 17, although of course other techniques may also be used. For thetechniques of FIGS. 18–19, the turret 610 is modeled as a series ofpoints PO . . . PN. For example, the point PO may be at the base 624,and the point PN may be located at a tip of the nozzle 631 withadditional points (e.g., in the range of tens or hundreds) located alongthe arms 626–630 between the base 624 and the nozzle 631. Because theoverall geometry of the turret 610 is known (including the lengths ofthe arms 626–630), and because the angles θ1, θ2, θ3, θ4, θ5 and L1 aremeasured by the position sensors 634, and because the position of thepoints PO . . . PN is defined relative to the turret arms 626–630 (thatis, the position of a given point along a particular one of the arms626–630 is defined), the position of each point PO . . . PN in thevehicle coordinate system can be calculated at any time.

Referring first to FIG. 18, at step 691, the envelope control module 662computes the position for a particular point Pn (initially PO andincrementing through PN). After being calculated, the position of eachpoint Pn is then compared with the representation 671 of the permissibletravel envelope to assess the position of the turret 610 relative to thepermissible travel envelope. In one embodiment (FIG. 18), the positionof point Pn is simply compared at step 695 with the representation 671to assess whether the point Pn is inside or outside the permissibletravel envelope. In this embodiment, the permissible travel envelope isdefined sufficiently small such that a buffer zone exists between thepermissible travel envelope and the fire fighting vehicle 620. Thebuffer zone is made sufficiently large that enough time exists for theturret 610 to come to a complete stop after it has been detected thatthe turret 610 has left the permissible travel envelope and after thecontrol signals to the actuators 632 have been adjusted to stop movementof the turret 610, and further taking into account the maximumspeed/momentum of the turret 610. Therefore, in this embodiment, once itis determined at step 696 that the point Pn is outside the envelope, thecontrol signals transmitted to the actuators 632 are adjusted so as tocause the turret 610 to slow to a stop as soon as possible. Once theturret 610 comes to a stop, a warning is provided to the operator (e.g.,a flashing red light), and the operator is then permitted to manuallyoverride the envelope control module 662 and move the turret 610 backinto the permissible travel envelope. Alternatively, the turret motioncontroller 660 may provide control signals to the actuators 632 whichcause the actuators 632 to retrace their values before leaving thepermissible travel envelope, so that the turret 610 is automaticallyreturned to the permissible travel envelope. If the point Pn is notoutside the permissible travel envelope, then n increments and theprocess is performed again for the next point Pn+1 along the turret 610(steps 697 and 698).

In another embodiment, the envelope control module 662 takes intoaccount the velocity of the turret 610 and causes the turret 610 to slowdown before reaching the edge of the permissible travel envelope. Thisallows the permissible travel envelope to be defined so as to encompassmore of the overall range of motion of the turret 610, because it is notnecessary to define the permissible travel envelope with a large bufferzone between the permissible travel envelope and the fire fightingvehicle 620.

To this end, a turret velocity is calculated, for example, bysubtracting the previous position from the current position and dividingby the amount of time elapsed (e.g., a control logic update cycle) sincethe position for the point Pn was previously calculated. Preferably, theturret controller 660 is implemented such that the processes of FIGS.17–18 (as well as FIG. 17 and FIG. 19) is performed once per updatecycle of the control logic that implements the turret controller 660,with the update cycles occurring at fixed intervals, e.g., every fewhundred microseconds or less. The foregoing calculation results in avelocity vector since the turret position is known in three dimensions.It may also be desired to calculate an average velocity vector byaveraging the instantaneous velocity vector over numerous update cyclesto reduce the effects of noise. Further, it may also be desirable tocalculate an acceleration vector if a higher level of sophistication isrequired.

Based on the velocity, multiple representations 671 of the permissibletravel envelope are then used and compared against the actual positionof the turret 610. For example, a multi-tier comparison scheme may beused wherein each point is compared to multiple representations 671 ofthe permissible travel envelope at step 695. Depending on whichenvelopes a given point Pn is determined to have exited at step 696, awarning may be provided to the operator (e.g., a flashing yellow light)and the turret 610 may be caused to slow down (for an inner envelope),or the turret 610 may be brought to an immediate stop (for an outerenvelope). Whether a particular envelope merely causes a warning lightor instead causes the turret 610 to be brought to a stop is then variedas a function of the speed of the turret 610.

FIG. 19 shows another embodiment in which the velocity and accelerationof the turret 610 are computed in real time to obtain a dynamicassessment of the motion of the turret 610 relative to the permissibletravel envelope. FIG. 19 is similar to FIG. 18 and includes many of thesame steps of FIG. 18. Only the steps that are different will bediscussed.

Thus, in FIG. 19, at step 692, the velocity and acceleration of theturret 610 are computed for each of the points PO . . . PN. For eachpoint, at step 693, the turret motion controller 662 then computes astop distance, or the minimum amount of distance that would be traveledby the point Pn were the turret 610 brought to a stop, based on thecurrent velocity and acceleration of the point Pn. At step 694, thedistance between the turret 610 and the permissible travel envelope isthen computed along the current trajectory of the point Pn, and thisstop distance is then compared at step 695 to the envelope distance tothe determine a margin therebetween. At step 696,′ if the margin isbelow a predetermined threshold, then the turret motion controller 662brings the turret 610 to an immediate stop and operates in generally thesame manner as described in the above when the turret 610 enters thebuffer zone. Alternatively, the turret motion controller 660 may adjustthe motion of the turret 610 to permit the turret 610 to continue movingwithout leaving the permissible travel envelope. For example, if theoperator is commanding the turret 610 to move down and to the left, butmotion to the left would cause the turret 610 to collide with a portionof the fire fighting vehicle 620, then the turret motion controller 660may operate so as to cause downward but not leftward movement of theturret 610. In another alternative embodiment, when the turret 610 istraveling towards an edge of the permissible travel envelope,multi-tiered threshold levels may be used to cause the turret 610 toslow as the turret 610 nears the edge of the permissible travelenvelope, in a manner akin to the multi-tiered envelopes describedabove.

It may be noted that the permissible travel envelope is smaller than thesize of the overall range of motion of the turret 610. Any range ofmotion beyond the overall range of motion is inherently excluded in thepermissible travel envelope. Because the turret 610 cannot physicallytravel beyond the range of motion, the permissible travel envelopealready inherently excludes this space and there is no need to modelthis space. To the extent that certain ranges of motion are excluded(e.g., certain combinations of angles or XYZ positions are not allowed)the permissible travel envelope is necessarily smaller than the overallrange of motion.

According to another embodiment, the permissible travel envelope may bedetermined and stored in real time. For example, a plurality of sensors(e.g., ultrasonic sensors) may be mounted to the turret 610 to providethe turret controller 660 with information regarding approachingobstructions. This permits the permissible travel envelope to be definedin a manner which takes into account obstructions 625 that are not partof the vehicle 620 and therefore are not necessarily known in advance ofwhen the vehicle 620 arrives at the scene of a fire. Thus, if the turretcontroller 660 detects an obstruction within a predetermined distance ofthe turret 610, the turret controller 660 may bring the turret 610 to astop or alter the path of movement of the turret 610. A combination ofthis approach and the approaches described above may also be used. Otherembodiments and combinations are also possible.

2. Turret Targeting

The turret controller 660 preferably also assists turret targeting. Forexample, a human operator controlling a turret at the scene of a firemay not be able to identify the location of the “hot spot” (i.e. thecenter of a fire). The operator may have obscured vision from smoke,debris, buildings, etc, thereby reducing the effectiveness of the turretand the fire fighting agent. The turret controller 660 providescapabilities to identify the location of a hot spot or other desiredlocation in a fire, and target the turret 610 on that spot when theturret operator may not be able to do so. Also, the operator may not beable to view the orientation of the nozzle, nor the direction nozzle ispointing towards due to smoke, debris, buildings, or other suchobstacles. The turret controller 660 identifies the desired location ina fire, and targets the turret 610 on that spot when the operator of theturret 610 may not be able to do so.

The turret control system 612 includes the fire position indicator 635,as shown in FIG. 16. The fire position indicator 635 providesinformation indicative of a spatial location or position of a selectedregion of a fire or other region of interest. In an exemplaryembodiment, the fire position indicator 635 is indicative of the spatialposition of a selected region of a fire provided in coordinates (i.e.height, width, and depth coordinates such as X, Y, and Z Cartesiancoordinates, or other such position indication systems) using a vehicleframe of reference. Alternatively, the fire position indicator 635 maybe provided in two dimensional coordinates such as X, Y coordinates.Other non-Cartesian coordinate systems or other position indicatorsusing other frames of reference may alternatively be used.

Various devices may be used to implemented the fire position indicator635. In an exemplary embodiment, the fire position indicator 635indicates the hottest region within a fire (typically the center or hotspot) and is implemented using a heat detection device. Alternatively,the fire position indicator 635 may use a laser detection device forlaser-guided tracking. According to this latter approach, an area ofinterest may be identified (e.g., by directing the laser at a portion ofa building immediately adjacent the region of interest), and the nozzle631 can be targeted on, and can track, the area of interest of a fire.The heat detection and laser tracking approaches are now described ingreater detail, although it will be appreciated that these approachesare merely exemplary embodiments of the fire position indicator 635 inthe system of FIG. 16.

Referring first to FIG. 20, in one embodiment, the fire positionindicator 635 is implemented using a heat detection system 727. The heatdetection system 727 includes one or more heat sensitive cameras 728. Inan exemplary embodiment, the camera 728 is an infrared camera or otherinfrared imaging device which produces two dimensional (2-D) image data,although other heat sensitive devices may also be used. The image iscomprised of individual pixels, each pixel having a pixel intensity orcolor that is a function of temperature or temperature differential fora corresponding location in the 2-D field of view. Infrared heatcamera(s) advantageously offer the ability to penetrate smoke to locatethe fire source. For example, the location of the fire may not bevisible with the naked eye due to the amount of smoke, debris,buildings, or other things which may obscure a visual sighting of thefire location. The infrared camera 728 is used to allow the turretcontroller 660 to “see” a hot spot or other area of interest.

The heat sensitive camera 728 may be placed in a variety of locations onthe fire fighting vehicle 620. In an exemplary embodiment, the heatsensitive camera 728 is mounted to the fire fighting vehicle 620. Inother exemplary embodiments, the heat sensitive camera 728 may beprovided proximate the nozzle 631 of the turret 610, or on the roof ofthe fire fighting vehicle 620.

In a preferred embodiment, two heat sensitive cameras, 728 a and 728 b,are used. The heat sensitive camera 728 a is used to provide a widefield of view for the targeting system, i.e., to identify the generallocation of the fire or trouble spot. The camera 728 a has a wide fieldof view and is used to determine the general area where turret should bepointed (“gross positioning”). Preferably, the camera 728 a is mountedon the vehicle chassis in a manner such that the coordinate system ofthe camera 728 a is aligned with the vehicle coordinate system describedabove in connection with the envelope control module 662 and shown inFIG. 13. Specifically, in the vehicle coordinate system shown in FIG.13, the X-axis is aligned along the width of the vehicle 620, the Y-axisis aligned along the height of the vehicle 620, and the Z-axis isaligned along the length of the vehicle 620. The camera 728 a preferablyhas an imaging plane which is parallel with the plane defined by the Xaxis and the Y-axis of the vehicle coordinate system. For example, theorigin of the vehicle coordinate system is defined to be the samelocation on the vehicle 620 where the camera 728 a is mounted. For grosspositioning, this allows the image data from the camera 728 a to beprocessed to obtain a quick assessment of the location of the hot spot.For example, if the hot spot appears in the middle of the image data,then the nozzle 631 should be pointing straight ahead. Conversely, ifthe hot spot appears on the left side or right side of the image data,then the nozzle 631 should be pointed to the left or right,respectively.

The heat sensitive camera 728 b is used to fine tune the position orlocation indication of the hot spot of the fire (“fine positioning”).Preferably, the camera 728 b is mounted on or near the nozzle 631 of theturret 610, and is mounted so as to be aligned with the flow directionof the fire fighting agent from the nozzle 631. Specifically, the firefighting agent flowing from the nozzle 631 preferably travels along anaxis (Z-axis) which is perpendicular to the 2-D (X-Y) imaging plane ofthe camera 728 b. (The camera 728 b is assumed to have an XYZ coordinatesystem which is, in general, not aligned with the XYZ coordinate systemof the vehicle 620, although the two may be considered aligned when theturret nozzle 631 is level and pointing straight forward.) Given thatthe distance between the center of the 2-D image plane of the camera 728b and the center of the stream of fire fighting agent is small relativeto the distance between the camera 728 b and the fire, it may be assumedthat the center of the 2-D image plane of the camera 728 b and thecenter of the stream of fire fighting agent are located at the samepoint. Therefore, when the hot spot appears on the left side of theimage data, the turret needs to be moved to the left to be aimed at thehot spot. With this configuration, it is known that the turret ispointed at the hot spot of the fire so long as the hot spot appears inthe center of the image data. It may be noted that conventional turretsdispense fire extinguishing agent at a sufficiently high velocity suchthat it may be assumed that fire extinguishing agent dispensed from ahorizontally oriented turret will not travel appreciably downwardlybefore reaching the target. Therefore, fire extinguishing agent reachesthe hot spot if the turret 610 is pointed at the hot spot. As detailedbelow, a control algorithm may then be executed which maintains the hotspot located at the center of the image data for the camera 728 b.

In an alternative embodiment, in addition to the camera 728 b, one ormore additional cameras may be mounted around the perimeter of thenozzle 631. The use of multiple cameras on the nozzle 631 allowsportions of image data from the multiple cameras to be processed as asingle image, so that the any obstructions caused by the presence of thenozzle 631 and the stream of fire fighting agent may be avoided.

Once the heat detection system 727 has identified the location of thearea of interest in the fire in the image data, the heat detectionsystem 727 uses a conversion module 729 to convert the location of thearea of interest in the image data into position information for use bythe turret controller 660 in controlling the turret 610, as will bedescribed in greater detail below. For each of the cameras 728 a and 728b, the conversion module 729 provides the turret controller with X,Yvalues indicative of the distance (magnitude and polarity) of the hotspot from the center of the image data produced by the respective camera728 a, 728 b (with the X,Y values being provided in the respectivecoordinate systems of the cameras 728 a and 728 b). The conversionmodule 729 may also be integrated into the turret controller 660, suchthat the cameras 728 a and 728 b provide the turret controller 660 withraw image data an the turret controller 660 determines theabove-mentioned distances. The operation of the turret targeting module664 is discussed in greater detail below.

Use of the heat detection system 727 permits a hot spot of the fire tobe continuously tracked and allows the aiming of the turret 610 to beadjusted in accordance with movement of the hot spot. This increases theefficiency of the fire fighting agent by placing the fire fighting agenton the area that may need it the most (i.e. the active hot spot of thefire) rather than being placed on a cold or less active region of thefire.

Referring now to FIG. 21, in another embodiment, the fire positionindicator 635 is implemented using a laser tracking system 730. In anexemplary embodiment, the laser system 730 includes a laser designator732 and a laser detector 734 as shown in FIG. 21.

The laser tracking system 730 is similar in concept to those used inguidance systems such as missile guidance systems. The laser designator732 is a handheld pointing device capable of being held by an operatorand pointed at region of interest, e.g., at or near a desired targetarea of a fire. The laser designator 732 provides an area or spot oflaser light on or near the target. The target reflects and scatters thelaser light spot. The laser detector 734 is preferably a camera which issensitive to particular wavelengths of light (i.e. the wavelengthsassociated with the laser designator 732), and excluding otherwavelengths. The laser detector 734 is capable of receiving the laserlight designating the region of interest after the laser light isreflected from the region of interest. When the laser detector 734detects the laser light, the laser light spot appears at a particularlocation in the image data acquired by the laser detector 734, with thelocation of the laser light spot in the image data being a function ofthe position of the reflected laser light spot relative to the laserdetector 734.

In a preferred embodiment, two laser detectors, 734 a and 734 b, areused. The preferred configuration is generally the same as thatdescribed in connection with the cameras 728 a and 728 b. Thus, thelaser detector 734 a is used for gross positioning and is mounted to thefire fighting vehicle so as to be aligned with the vehicle coordinatesystem shown in FIG. 13. The laser detector 734 b is mounted to thenozzle 631 and has an imaging plane which is perpendicular to the streamof fire fighting agent dispensed by the nozzle 631. Alternatively,multiple laser detectors may be mounted to the nozzle 631, similar tothe arrangement described above. Once the laser detection system 730 hasidentified the location of the area of interest in the fire in the imagedata, the laser detection system 730 uses a conversion module 735 toconvert the location of the area of interest in the image data intoposition information for use by the turret controller 660 in controllingthe turret 610, as will be described in greater detail below. For eachof the detectors 730 a and 730 b, the conversion module 735 provides theturret controller with X,Y values indicative of the distance (magnitudeand polarity) of the laser spot from the center of the image dataproduced by the respective camera 730 a, 730 b. The conversion module735 may also be integrated into the turret controller 660.

Referring back to FIG. 16, the operation of the turret targeting module664 will now be described. In the turret targeting mode of operation,the turret targeting module 664 and the envelope control module 662 inFIG. 16 are active, and the remaining modules 665, 668, 670, 672, and674 are inactive. The targeting module 664 module receives the positioninformation from the fire position indicator 635 and, based on theposition information, determines whether the nozzle 631 should be movedup, down, to the left, to the right, or some combination thereof. Theturret targeting module 635 then generates signals that simulate inputsignals from the joysticks 619, and these signals are provided to theenvelope control module 662. The envelope control module 662 operates inthe manner previously described, except that inputs are received fromthe turret targeting module 664 rather than from one of the operatorinterfaces 616. Thus, assuming the turret 610 is within the permissibletravel envelope, the envelope control module 662 relays these signals tothe actuators 632; otherwise, the envelope control module 662 intervenesto cause the turret 610 from leaving the permissible travel envelope.

Referring now to FIG. 22, a flowchart describing the operation of theturret targeting module 664 is illustrated. For simplicity, it isassumed in the following discussion that θ1 is fixed (the base 624 isheld stationary) and θ5 is allowed to vary (the third arm 630 ishingedly moveable). Of course, a non-stationary base 624 may also beused.

At step 751 it is determined whether the target is in the imagegenerated by the turret mounted camera (either the camera 728 b or 734b). If the target happens to be within the field of view of the turretmounted camera, then the process proceeds directly to step 756,described in greater detail below.

Assuming the target is not within the field of view of the turretmounted camera, then the process proceeds to step 752. At step 752, anestimate of the position (XT, YT, ZT) of the target is developed basedon the image data from the gross positioning camera 728 a or 734 a. The(XT, YT, ZT) value is considered to be an estimate because the accuracyof the value is limited by the fact that the value is generated based oninformation from a single camera and therefore depth perception islimited. In an alternative embodiment, it may be desirable to usemultiple cameras mounted on the vehicle body in order to allow a moreaccurate (XT, YT, ZT) value to be obtained and/or to allow the turretmounted cameras to be eliminated. It is assumed that the fire fightingvehicle 620 is pointed generally in the direction of the target, andthat the field of view of the camera 728 a or 734 a is sufficientlylarge that the target will be within the field of view of the camera 728a or 734 a. However, if the target is not within the field of view ofthe camera 728 a or 734 a, then an error is issued and it is necessaryto reposition the fire fighting vehicle 620 if it is desired to use theturret targeting module 664. In an alternative embodiment, the camera728 a or 734 a is mounted for rotation and/or other movement to improvethe target-locating ability of the camera 728 a or 734 a.

Assuming the target is within the field of view of the gross positioningcamera 728 a or 734 a, then, at step 753, the turret 610 is brought to aposition (θ 1 , θ 2 , θ 3 , θ 4 , θ 5 , and L) at which it is expectedthat the turret 610 will be aimed at the target. At this point, thetarget should be within the field of view of the fine positioning camera728 b or 734 b. At step 754, it is determined whether the target is infact within the field of view of the fine positioning camera 728 b or734 b. For example, for the heat detection system 727, it may beascertained whether the fine positioning camera 728 b is viewing aregion of the same temperature as the hot spot identified by the camera728 a. For the laser tracking system 730, it may be ascertained whetherthe fine positioning camera 734 b is viewing light within the range ofwavelengths of the laser light emitted by the laser designator 732. Ifthe target is not within the field of view of the fine positioningcamera 728 b or 734 b, the turret controller 660 is programmed to entera search mode (step 755) in which the turret controller 660 causes theturret 610 to move in a region surrounding the position (θ 1 , θ 2 , θ 3, θ 4 , θ 5 , and L) at which it is expected that the turret 610 will beaimed at the target. The turret controller 660 then keeps moving theturret 610 until the target enters the field of view of the finepositioning camera 728 b or 734 b.

Once the target is within the field of view of the fine positioningcamera 728 b or 734 b, the turret controller 660 attempts to center thetarget within the field of view of the fine positioning camera 728 b or734 b. For example, if it is assumed that ΔX is the deviation of thetarget from the center of the field of view of the fine positioningcamera 728 b or 734 b in the X dimension, and that ΔY is the deviationof the target from the center of the field of view of the finepositioning camera 728 b or 734 b in the Y dimension (where the Xdimension and the Y dimension are defined in terms of the coordinatesystem of the fine positioning camera 728 b or 734 b), then ΔX and ΔYmay be used as feedback values in two respective feedback control loops.For example, if θ 1 , θ 2 , θ 3 , and L are held constant, then afeedback control loop which varies θ 5 (nozzle left/right) to minimizeΔX and another feedback control loop which varies θ 4 (nozzle up/down)to minimize ΔY may be employed. Thus, the position and orientation ofthe nozzle 631 is adjusted such that the nozzle 631 is aimed at theregion of interest and, at the same time, fire extinguishing agent isdispensed toward the region of interest. Because this arrangement isimplemented in the form of feedback control loops, the location of theregion of interest may be continuously tracked and the position andorientation of the nozzle 631 may be continuously adjusted in responseto movement of the region of interest (for example, due to cooling of ahot spot when fire extinguishing agent is dispensed on the hot spot).Therefore, the nozzle 631 may remain pointed at the region of interestduring movement of the region of interest.

When the turret targeting module 664 is used, expanded fire fightingcapabilities for the turret 610 are achieved. Using the fire positionindicator 635 to view the fire, and determine the location of the areaof interest of the fire, improves the aim and effectiveness of theturret 610 in many situations.

3. Turret Pan, Turret Deploy, and Turret Store

Referring again to FIG. 16, in addition to the envelope control module662 and the turret targeting module 664, the turret motion controller660 further includes a learn module 665 which is used in connection witha turret pan module 668, a turret deploy module 670, and a turret storemodule 672. The modules 665, 668, 670, 672 permit the turret controller660 to store information such as position information and then controlmovement of the turret 610 in accordance with the stored information.

First, the learn module 665 and the turret pan module 668 will bedescribed. At the scene of a fire, it is sometimes desirable to simplypan a turret back and forth across a general region. The turret panmodule 668 causes the turret 610 to move in a predetermined patternwhile the turret 610 dispenses a fire fighting agent toward the fire. Inthe pan mode of operation, the modules 665, 670, 672, and 664 as well asthe fire position indicator 635 are not active in FIG. 16. The envelopecontrol module 662 may be active as previously described.

In one embodiment, panning may be implemented by programming the panmodule 668 to simulate inputs from the operator interface 616. Forexample, for a simple back and forth pattern, the operator may bepermitted to bring the turret 610 to a region of interest, and then theturret pan module 668 may generate signals based on stored informationthat cause the actuator 632 f to oscillate left and right. For acircular pattern, the actuator 632 e may also be used. To provideflexibility, operator inputs may be received that are used to controlthe amount of angular displacement and/or the amount of time the turretmoves in one direction (and therefore the distance traveled) beforereversing course. Alternatively, operator inputs may be simulated bystoring operator inputs as the operator moves the turret 610 in adesired pattern, and then retrieving the stored operator inputs andusing the stored operator inputs to generate additional control signalsfor the actuators 632 so as to cause the turret to repeat the patterncreated in response to the original inputs. In these embodiment, in FIG.16, the summation element 679 and the gain block 674 are not used (thatis, the signals from the turret pan module 668 feed through directly tothe envelope control module 662 as simulated joystick signals).

In another embodiment, for maximum flexibility, the operator is allowedto program a pan pattern into the turret pan module 668, and feedbackcontrol is used to ensure that the turret 610 conforms to the programmedpattern. To this end, in an initial “learn” mode of operation, theturret controller 660 first learns the predetermined pattern bymonitoring operator inputs used to control movement of the turret 610.Specifically, and referring now to FIG. 23, FIG. 23 is a flowchartshowing the learning mode of the turret controller 660. At step 761,operator inputs are acquired by one of the operator interfaces 616. Atstep 762, the turret controller 660 moves the turret 610 in real time inaccordance with the operator inputs. At step 763, the position of theturret 610 is measured using the position sensors 634. At step 764, theposition information acquired during step 763 is stored in the turretpan module 668. The position information is stored as a series ofwaypoints formed of simultaneously measured θ1, θ2, θ3, θ4, θ5 and L1values. Step 764 may occur in response to operator inputs or may occurat regular intervals. For example, if step 764 occurs in response tooperator inputs, the operator may periodically press a “store” button toindicate to the turret controller 660 that the operator wants the turret610 to periodically return to its current position. In this embodiment,the waypoints are stored in the form of θ1, θ2, θ3, θ4, θ5 and L1 valueswhich are measured by the position sensors 634 at the time the operatorinput is received. The operator moves from position to position andpresses the store button until a series of waypoints are defined. Forback and forth movement, as few as two waypoints may be used. For a morecomplex motion profile, such as a figure eight motion profile, a seriesof waypoints may be used. Alternatively, in another embodiment, theturret controller 660 may automatically store the position informationat periodic intervals as the turret 610 is controlled in response tooperator inputs. The process of FIG. 23 is then repeated until anoperator input is received indicating that the operator has completeddefining the predetermined pattern. It may be noted that, as is the caseelsewhere throughout this description, although steps 761–764 are shownas a series of steps to be performed, the steps 761–764 need notnecessarily be performed at the same update rate and therefore need notnecessarily be sequentially performed.

In one embodiment, the operator is provided with a user interface thatallows the operator to program an oscillate range and that also providesvisual feedback regarding the selected oscillate range. For example, thedisplay 618 may display one or more bars that indicate a programmedrange of oscillation. For example, if the nozzle 631 is to remain levelbut oscillate back and forth to the left and right, one bar may be usedto indicate a range of oscillation to the right from center and anotherbar may be used to indicate a range of oscillation to the left fromcenter. Alternatively a single bar centered about zero degrees may beused. Operator inputs (e.g., operator touches on a keypad) may be thenreceived that cause the turret pan module 668 to vary the range ofoscillation in accordance with the operator inputs, and also to updatethe status bars to reflect the newly programmed range of oscillation. Ifdesired, this information may be stored in non-volatile memory andavailable upon system power up, and reset and default buttons may alsobe provided to allow the turret pan module 668 to revert to a defaultsetting. Control of turret movement may then be effected, for example,through the use of simulated joystick inputs or position waypoints, aspreviously described.

Referring now also to FIG. 24, in a second mode of operation, the turretcontroller 660 causes the turret 610 to repetitively move in accordancewith the predetermined pattern programmed during steps 761–764. Thus, atstep 766, one of the series of waypoints stored during step 764 isprovided as input to a feedback control system. The θ1, θ2, θ3, θ4, θ5and L1 values of the active waypoint are used as position command inputsin a position feedback control loop implemented in part by the turretmotion controller 660. Referring to FIG. 25, FIG. 25 shows the feedbackcontrol system of FIG. 16 in greater detail. For simplicity, the modules662, 664, 665, 670, and 672 are not shown in FIG. 25. The feedbackcontrol system comprises one feedback control loop for each axis ofmovement. The θ1, θ2, θ3, θ4, θ5 and L1 values as position commandinputs to a series of summation elements 679 a–679 f (shown collectivelyin FIG. 16 as the summation element 679). Each of the position sensors634 a–634 f measures the θ1, θ2, θ3, θ4, θ5 and L1 values (step 727).These measurements are provided to the summation elements 679 a–679 f,which compare the measured turret position with the position informationreceived from the turret pan module 668. The output of each summationelement 679 a–679 f is a position error signal and is provided to arespective gain block (e.g., a proportional-integral block) 674 a–674 f.The outputs of the P1 blocks 674 a–674 f are used as output signal for arespective one of the actuators 632 a–632 f. The feedback control loopcontrols the turret so as to reduce a difference between the measuredposition of the turret and the active waypoint. When the turret 610 isbeginning to approach the active waypoint, a new waypoint is provided bythe turret pan module 668 to the summation elements 679 a–679 f, suchthat the turret 610 is successively delivered to the series ofwaypoints. When the final waypoint is reached, the process repeatsstarting with the first waypoint.

The arrangement of FIGS. 23–25 allows the shape and time-profile of thepanning pattern to be fully configurable and fully programmable,especially if the waypoints are stored at regular intervals rather thanin response to operator inputs. Specifically, the operator is permittedto move the turret 610 so as to aim the turret at a particular location(e.g., hot spot) of the fire, linger at the particular location, andthen move the turret to the next location (e.g., another hot spot). Theturret controller 660 is then able to move the turret 610 to each of thehot spots, regardless whether they are aligned with each other, andcause the turret 610 to linger at each hot spot in the same manner andfor the same amount of time as originally programmed by the operator.

The turret deploy module 670 is used to deploy the turret from a storeposition in which the turret 610 is stored for vehicle travel to adeploy position in which the turret 610 deploys a fire fighting agent.Typically, the turret 610 is stored in a locked position during travelof the fire fighting vehicle 620. Upon arrival to the scene of a fire,the turret deploy module 670 allows the turret 610 to be deployed to apredetermined position with minimum operator involvement.

The turret deploy module 670 operates in a manner which is generallysimilar to the turret pan module 668. The turret deploy module 670 maystore a sequence of control signals to be provided to the actuators 632or may store a series of position waypoints that are sequentiallyprovided to multiple feedback control loops, as previously described.The turret deploy module 670 may be preconfigured before vehicledeployment and/or may be configured by an operator. For example, if theturret deploy module is preconfigured, one or more deploy positions maybe preprogrammed in the turret deploy module 670. If the turret deploymodule 670 is configured by the operator, one or more deploy positionsor deploy movement patterns may be stored by the operator as describedabove in connection with the turret pan module 668. The turret deploymodule 670 may also provide the operator with the ability to enter adesired position and orientation of the nozzle 631 relative to thevehicle 620. This allows the operator to define the desired deployposition as the vehicle 620 approaches the scene of a fire in situationswhere information regarding the scene of the fire is known prior tovehicle arrival at the scene of the fire.

Upon arriving at the scene of a fire, an operator input is receivedindicating that the operator wishes to turret deploy the turret 610.Turret deployment may begin immediately or, for fire fighting vehicleswith outrigger assemblies, turret deployment may be programmed to beginautomatically after outrigger deployment is complete. If the turretdeploy module 670 stores simulated joystick commands, the turret 610 maybe deployed by retrieving the stored information and using theinformation to generate control signals provided to the actuators 632 byway of the envelope control module (with the summation element 679 andthe PI gain block 674 being inactive). If the turret deploy modulestores θ1, θ2, θ3, θ4, θ5 and L1 values for the deploy position, thesevalues may be provided to the feedback control loops shown in FIG. 25 tocause the turret controller 660 to move the turret 610 to the deployposition in closed loop fashion. A series of θ1, θ2, θ3, θ4, θ5 and L1values (waypoints) may also be used if a particular deploy trajectory isdesired.

The turret store module 672 is used to move the turret 610 from a deployposition in which the turret is positioned to dispense a fire fightingagent on a region of interest to a store position in which the turret isstored for vehicle travel. Turrets mounted on top of fire fightingvehicles are often stored between the emergency lights. Therefore, theemergency lights are particularly susceptible to damage during theprocess of storing the turret, given the proximity of the turret to theemergency lights. The turret store module 672 avoids such damageassisting storage of the turret 610. For example, in one embodiment, theturret store module 672 stores the θ1, θ2, θ3, θ4, θ5 and L1 values forthe store position, these values are provided to the feedback controlloops shown in FIG. 25 to cause the turret controller 660 to move theturret 610 to the store position in closed loop fashion. A series of θ1,θ2, θ3, θ4, θ5 and L1 values (waypoints) may also be used if aparticular store trajectory is desired which avoids damaging otherstructure on the vehicle 620. Once the turret 610 reaches the storeposition, the turret store module 672 causes an actuator to engage whichis coupled to a lock mechanism. This allows the turret 610 to be lockedin place after the turret 610 reaches the store position with minimaloperator involvement.

The turret controller 660 may also be used to implement other features.For example, the turret controller 660 may be used to implement annozzle leveling feature in which the nozzle 631 is maintained in thehorizontal position regardless of boom angle. This allows the nozzle 631to remain aimed at a fire during boom movement.

4. Operator Interface

Referring now to FIG. 26, an embodiment of the control system 612 isshown wherein two turrets 731 and 732 are provided. Both turrets operatein the same manner as the turret 610, although at least one of theturrets 731, 732 may be constructed differently and may be mounted in adifferent location, such as a bumper turret mounted on a bumper of thefire fighting vehicle 620. Also shown are the operator interfaces 616and the turret controller 660, which includes structure that duplicatesthe structure shown in FIG. 16 for the additional turret. (That is,duplicate turret controllers 660, operating in parallel and respectivelycoupled to the turrets 731, 732, are used. For simplicity, a singleturret controller 660 is shown in FIG. 26.)

As previously noted, the operator interfaces 616 each include respectivejoysticks 619 a and 619 b. Typically, the joysticks 619 a, 619 b may bemounted at different locations on the vehicle (such as in the cab and aton operator panel elsewhere on the vehicle) and therefore one of thejoysticks 619 a, 619 b may be at a location that has better visibilitythan the location of the other of the joysticks 619 a, 619 b. Eachjoystick 619 a, 619 b is coupled to respective interface modules 613 cand 613 d, and there is no inherent difference between the joysticks 619a, 619 b other than vehicle location.

In order to take advantage of the multiple joysticks, the turretcontroller 660 is capable of reconfiguring itself (e.g., in response tooperator inputs) to thereby provide the operator with the ability to useeither of the joysticks 619 to control either of the turrets 771, 772.Thus, in a first mode of operation of the turret controller 660, theturret controller 660 controls the position and orientation of thenozzle of the turret 771 based on operator inputs acquired by thejoystick 619 a, and controls the position and orientation of the nozzleof the turret 772 based on operator inputs acquired by the joystick 619b. In a second mode of operation, an opposite arrangement may be used(wherein the turret controller 660 controls the position and orientationof the nozzle of the turret 771 based on operator inputs acquired by thejoystick 619 b, and controls the position and orientation of the nozzleof the turret 772 based on operator inputs acquired by the joystick 619a.) In a third mode of operation, the turret controller 660 controls theposition and orientation of the nozzles of both the turrets 771 and 772based on operator inputs acquired by a single one of the joysticks 619a, 619 b. In other words, both turrets 771, 772 are synchronized to thesame joystick 619 a or 619 b. This allows both turrets 771, 772 to beaimed at different areas but move in tandem in response to operatorinputs from a single joystick 619 a or 619 b, for example, when panningthe turrets back and forth near a region of the fire. Alternatively, theturret controller 660 may be configured to control a first one of theturrets 771, 772 directly in response to operator inputs and to controla second one of the turrets 771, 772 such that the second turret 771,772 tracks movement of the first turret 771, 772 and dispenses firefighting agent on the same location as the first turret 771, 772. Thedisplay 618 a, 618 b associated with each of the respective joysticks619 a, 619 b is used to indicate to the operator the currentconfiguration of the turret controller 660, that is, which joysticks 619a, 619 b are useable to control which turrets 771, 772.

Also shown in FIG. 26 is an additional operator interface 773 whichincludes an additional joystick 774 and an additional display 775. Theoperator interface 773 is identical to the operator interfaces 616, andoperates in the same manner as the operator interfaces 616, except thatit is coupled to the control system 612 by way of a wireless (e.g.,radio-frequency) communication link. According to one embodiment, theadditional operator interface 773 is implemented using a personaldigital assistant or other handheld computer and joystick operation issimulated using a touch screen interface of the handheld computer. Thisallows an operator to have significant mobility at the scene of a firewhile controlling one or both of the turrets 771, 772. Alternatively, ifthe network features described above in connection with FIGS. 34–67 areemployed of U.S. Prov. No. 60/360,479 and U.S. Ser. No. 10/326,907, thenthe wireless communication link of FIG. 26 may be a wireless connectionthat is implemented using the Internet. For example, with reference toFIG. 34 of U.S. Prov. No. 60/360,479 and U.S. Ser. No. 10/326,907, thiswould allow an operator viewing the display 148 at the dispatch station116 or fire fighting facility to view the fire in progress and use theremote operator interface 773 to control one or both of the turrets 771,772. For municipalities with multiple fire stations, this allows themunicipality to have a fire fighter from any fire station assist in thefire fighting effort without necessarily having the fire fighter travelto the scene of the fire.

Referring again to FIG. 16, in another embodiment, in order to provideimproved operator feedback, the displays 618 provide a rendering of theposition and orientation of turret 610 relative to the remainder of thevehicle 620. As previously noted, in some cases, it is difficult for anoperator to see the exact location and orientation of the turret 610,for example, because smoke obscures the operator's vision, or becausethe operator is located inside an operator compartment of the firefighting vehicle and the position/orientation of the turret 610 is notvisible inside the operator compartment. This problem is exacerbated ifthe control system 612 cannot accurately respond to operator commandsbecause the water pressure is so great that the actuators 632 do nothave the power to overcome the water pressure and move the turret 610.

To address this problem, the real-time position of the turret 610acquired by the position sensors 634 is used by the turret controller660 to calculate the position and orientation of the arms 626–630 aswell as the nozzle 631. Based on this information, the turret controller660 generates image data for one or both of the displays 618 whichcauses the display 618 to provide a rendering of the position andorientation of each arm 626, 628, 630 of the turret 610 relative to thefire fighting vehicle 620. Multiple display regions may be used todisplay the position and orientation of the nozzle 631 and the positionand orientation of the arms 626–630. Alternatively, a single 3-Drendering may be displayed. Preferably, operator inputs may be receivedthat allow the turret 610 and the vehicle 620 to be viewed fromdifferent angles. A sensor (e.g., dual camera or ultrasonic array) maybe used to gather data useable to depict other objects such as buildings(in the case of municipal fire fighting vehicles) or airplanes (in thecase of ARFF vehicles) on the display 618.

In another embodiment, shown in FIG. 27, the turret controller 660includes a turret flow rate feedback control loop 781 as shown. Theturret flow rate control loop 781 is used to maintain constant flow rateof fire extinguishing agent from the turret nozzle 631 by compensatingfor various vehicle parameters. A number of vehicle parameters may varyand, as a result, cause a variation in the flow rate of the fireextinguishing agent. For example, in a pump and roll situation, the firetruck is pumping water and moving at the same time (e.g., to move thefire truck closer to the fire). The varying engine RPM and diversion ofpower to the drive train causes variations in pressure which in turncause significant variations in flow rate. The flow rate control loop781 adjusts the flow rate to make the flow rate constant even when theengine RPM varies.

Block 782 stores information pertaining to an operator input pertainingto flow rate. As indicated by block 782, the desired flow rate iscontinuously adjustable to provide a wide range of available flow rates.A feedback sensor 783 obtains flow rate feedback. The feedback sensor783 may be a flow rate sensor or a sensor that monitors a remainingamount of fire extinguishing agent, for example. Visual feedback (e.g.,a displayed flow rate) may then be provided to the operator using one ofthe displays 618.

In another embodiment, the turret control system 612 is at leastpartially self-calibrating. When a mechanical component of the turretassembly is replaced (such as one of the arms 626–630, position sensors634, or limit switches 636), the control system 612 recalibrates itselfin the field with a minimal amount of equipment. For example, tocalibrate a new position sensor 634, the turret controller 660 providescontrol signals to the corresponding actuator 632 to cause the actuator632 to move the turret to both limits of motion for the axis in whichthe position sensor 634 was replaced. Thus, if the position sensor 634 fis replaced, the turret controller 660 provides the actuator 632 f withcontrol signals that cause the actuator 632 f to move the turret arm 630full right and then full left. The new position sensor 634 f is thencalibrated by monitoring the output of the position sensor 634 f at thelimits of motion and storing this information.

In another embodiment, the operator interface 616 includes a voicerecognition module comprising voice recognition software or embeddedlogic to allow user inputs to be provided by the user in the form ofvoice commands and received by a suitable microphone or other pickupdevice. The voice recognition logic then interprets the voice commandsto produce suitable signals for controlling the turret 610. For example,rather than pushing up on the joystick 619, an operator may be providedwith the ability to state the word “up,” and the voice recognition logicthen interprets the word “up” spoken by the operator and in responseproduces an output that mimics the output produced by the joystick 619when the operator presses up on the joystick. The turret motioncontroller 660 then controls movement of the turret 619 in accordancewith the voice commands provided by the operator. In general, such avoice recognition module may be used to replace or supplement any of theoperator input devices described herein.

As previously indicated, the turret control system 612 of FIGS. 13–27may be combined with the other features described in of U.S. Prov. No.60/360,479 and U.S. Ser. No. 10/326,907. For example, in connection withparts ordering features, the limit switches 636 may be used to detectfailure of one or more of the position sensors 634, and/or the positionsensors 634 may be used to detect failure of one or more of the positionswitches 636. Upon detecting such failure, the control system 612 canproceed with ordering replacement parts.

Throughout the specification, numerous advantages of preferredembodiments have been identified. It will be understood of course thatit is possible to employ the teachings herein so as to withoutnecessarily achieving the same advantages. Additionally, although manyfeatures have been described in the context of a vehicle control systemcomprising multiple modules connected by a network, it will beappreciated that such features could also be implemented in the contextof other hardware configurations. Further, although various figuresdepict a series of steps which are performed sequentially, the stepsshown in such figures generally need not be performed in any particularorder. For example, in practice, modular programming techniques are usedand therefore some of the steps may be performed essentiallysimultaneously. Additionally, some steps shown may be performedrepetitively with particular ones of the steps being performed morefrequently than others. Alternatively, it may be desirable in somesituations to perform steps in a different order than shown.

As previously noted, the construction and arrangement of the elements ofthe turret control system shown in the preferred and other exemplaryembodiments are illustrative only. Although only a few embodiments ofthe present inventions have been described in detail in this disclosure,those skilled in the art who review this disclosure will readilyappreciate that many modifications are possible without materiallydeparting from the novel teachings and advantages of the subject matterrecited in the claims. Accordingly, all such modifications are intendedto be included within the scope of the present invention as defined inthe appended claims. In the claims, any means-plus-function clause isintended to cover the structures described herein as performing therecited function and not only structural equivalents but also equivalentstructures. Other substitutions, modifications, changes and omissionsmay be made in the design, operating conditions and arrangement of thepreferred and other exemplary embodiments without departing from thescope of the present inventions as expressed in the appended claims.

1. A fire fighting vehicle comprising: (A) a turret system, the turretsystem comprising (1) a turret nozzle, the turret nozzle being capableof dispensing a fire-extinguishing agent, and (2) an adjustable mountassembly that mounts the turret system to a remainder of the firefighting vehicle, wherein the adjustable mount assembly includes a firstarm, a second arm, and a third arm, the second arm being pivotablycoupled to the first arm and the third arm being pivotably coupled tothe second arm; (B) a turret control system, including (1) a firstoperator interface, (2) a second operator interface, (3) a plurality ofactuators, the plurality of actuators being coupled to the adjustablemount assembly and being capable of adjusting the positioning of theturret system to adjust the positioning of the turret nozzle relative tothe remainder of the fire fighting vehicle, and (4) a turret controller,the turret controller being coupled to receive operator inputs from thefirst and second operator interfaces, and the turret controller beingprogrammed to control the plurality of actuators based on the operatorinputs; wherein the turret controller is programmed to have first andsecond manual modes of operation; wherein, in the first manual mode ofoperation, the turret controller controls the position and orientationof the turret nozzle based on operator inputs acquired by the firstoperator interface; and wherein, in the second manual mode of operation,the turret controller controls the position and orientation of theturret nozzle based on operator inputs acquired by the second operatorinterface.
 2. The vehicle according to claim 1, wherein the turretsystem is a first turret system, the turret nozzle is a first turretnozzle, and the adjustable mount assembly is a first adjustable mountassembly; wherein the vehicle further comprises a second turret system,the second turret system including a second turret nozzle and a secondadjustable mount assembly, the second turret nozzle being capable ofdispensing a fire-extinguishing agent, the second adjustable mountassembly mounting the second turret system to a remainder of the firefighting vehicle; and wherein the turret controller is programmed tohave a third mode of operation in which the turret controller controlsthe position and orientation of both the first turret nozzle and thesecond turret nozzle based on operator inputs acquired by a single oneof the first and second operator interfaces.
 3. The vehicle according toclaim 2, wherein the turret controller is programmed to permit each ofthe first and second operator interfaces to be used to acquire operatorinputs to control either or both of the first and second turret systems.4. A fire fighting vehicle comprising: (A) a chassis and a vehicle bodymounted on the chassis, the chassis and vehicle body in combinationincluding an operator compartment capable of receiving a human operator,the operator compartment including steering and throttle controls forreceiving operator inputs to control movement of the fire fightingvehicle along a road; (B) a turret system including (1) an adjustablemount assembly, the adjustable mount assembly being mounted to thechassis and vehicle body combination, and the mount assembly including afire-extinguishing agent delivery system capable of transporting afire-extinguishing agent through the mount assembly; (2) a turretnozzle, the turret nozzle being mounted to the adjustable mountassembly, and the turret nozzle being capable of receiving thefire-extinguishing agent from the mount assembly; and (C) a turretcontrol system, the turret control system including a plurality ofactuators capable of adjusting the mount assembly to permit the positionand orientation of the turret nozzle to be adjusted and at least onesensor used to determine the position and/or orientation of theadjustable mount assembly, the turret control system further including amicroprocessor-based turret controller coupled to the plurality ofactuators, and the turret control system further including a displayhaving a screen, wherein the turret controller is programmed to drivethe display to provide a rendering of the turret system on the screen soas to display information pertaining to a position and orientation ofthe turret nozzle, the rendering being created based at least in part oninformation provided by the least one sensor.
 5. The vehicle accordingto claim 4, wherein the rendering is a three-dimensional rendering.
 6. Afire fighting vehicle comprising: (A) a chassis and a vehicle bodymounted on the chassis, the chassis and vehicle body in combinationincluding an operator compartment capable of receiving a human operator,the operator compartment including steering and throttle controls forreceiving operator inputs to control movement of the fire fightingvehicle along a road; (B) a turret system including (1) an adjustablemount assembly, the adjustable mount assembly being mounted to thechassis and vehicle body combination, and the mount assembly including afire-extinguishing agent delivery system capable of transporting afire-extinguishing agent through the mount assembly; (2) a turretnozzle, the turret nozzle being mounted to the adjustable mountassembly, and the turret nozzle being capable of receiving thefire-extinguishing agent from the mount assembly; and (C) a turretcontrol system, the turret control system including a flow rate actuatorcapable of adjusting a flow rate of fire extinguishing agent through theturret nozzle, the turret control system further including a turretcontroller coupled to the flow rate actuator, the turret controllerbeing programmed to implement feedback control of the flow rateactuator.
 7. The vehicle according to claim 6, wherein the turretcontroller is programmed to control the flow rate actuator to maintain aconstant flow rate.
 8. The vehicle according to claim 6, wherein theturret controller is programmed to acquire feedback informationpertaining to a supply of remaining fire extinguishing agent, and tomaintain constant flow rate despite variations in the supply ofremaining fire extinguishing agent.
 9. The vehicle according to claim 6,wherein the flow rate of the fire extinguishing agent is infinitelyadjustable.
 10. A fire fighting vehicle comprising: a first turretsystem; a second turret system; a first operator interface; a secondoperator interface; a turret control system, the turret control systemincluding a first plurality of actuators capable of adjusting theposition and orientation of the first turret system, the turret controlsystem including a second plurality of actuators capable of adjustingthe position and orientation of the second turret system, the turretcontrol system further including a microprocessor-based turretcontroller coupled to the first and second plurality of actuators,wherein the turret control system is programmed to permit operatorinputs acquired by the first operator interface to be used to controlthe first turret, the second turret, and the first and second turretsimultaneously; and wherein the turret control system is programmed topermit operator inputs acquired by the second operator interface to beused to control the first turret, the second turret, and the first andsecond turret simultaneously.
 11. A fire fighting vehicle comprising:(A) a chassis and a vehicle body mounted on the chassis, the chassis andvehicle body in combination including an operator compartment capable ofreceiving a human operator, the operator compartment including steeringand throttle controls for receiving operator inputs to control movementof the fire fighting vehicle along a road; (B) a turret systempositioned on a roof of the fire fighting vehicle, the turret systemincluding (1) an adjustable mount assembly, the adjustable mountassembly being mounted to the chassis and vehicle body combination, andthe mount assembly including a fire-extinguishing agent delivery systemcapable of transporting a fire-extinguishing agent through the mountassembly; (2) a turret nozzle, the turret nozzle being mounted to theadjustable mount assembly, and the turret nozzle being capable ofreceiving the fire-extinguishing agent from the mount assembly; and (C)a turret control system, the turret control system including a pluralityof actuators capable of adjusting the mount assembly to permit theposition and orientation of the turret nozzle to be adjusted and atleast one sensor used to determine the position and/or orientation ofthe adjustable mount assembly, the turret control system furtherincluding a microprocessor-based turret controller coupled to theplurality of actuators, and the turret control system further includinga display, wherein the turret controller is programmed to drive thedisplay to provide a rendering of the turret system so as to displayinformation pertaining to a position and orientation of the turretnozzle, the rendering being created based at least in part oninformation provided by the at least one sensor.
 12. The vehicleaccording to claim 11, wherein the rendering is a three-dimensionalrendering.